At the end of the day and on some level, Linux is Linux.
There are differences in default configuration, installer and package manager. Many people like a flavour of Ubuntu, I've never used it myself. In the past I used SuSE. You may want to try a couple of liveCDs and see which one gives you something you like.

I think NTFS has been read/write for a while now, but I'm not sure if that's all versions. Again, never used it.

I vastly prefer KDE, but if you want lightweight you probably want neither of those two.

I'm on ext4 at the moment.

Sortof. There are a number of standard directories for executables and where they go depends on what "group" an executable belongs to. Many UNIX programs (especially traditional programs) are small programs that do a single task. Large software packages (for instance, firefox) keep all their files together (typically in a directory under /opt or /usr/local) and symlink the executable in a default location.

Typical UNIX style is small programs that do one thing, and one thing only, but do it (extremely) well. Windows-style is more having one program that sortof does everything. That's a bit of a caricature, but you get the idea.

Configuration files go into /etc. Either programs have a configuration file (typically named something like programnamerc) or place their configuration data in a subdirectory. I think the latter is a more modern trend.
Per-user data is stored in the home directory, typically either in a file .programnamerc or in a directory .programname (note the dots).

If you want something really lightweight but still an "environment", give Razor-Qt a go. I put it on my old laptop, and it seems to work great so far. It's pretty simple, not a lot of features, but it runs with fairly little memory, and its far less broken than LXDE.

Debian stable with Xfce here. Lightweight enough for me. I had also tried a window manager without desktop manager (IceWM); too lightweight for me.
I'm using ext3, because I think there were some minor issues with ext4^[1]
The exact location where configuration is stored is one of the most prominent differences of Linux distro's (AFAIK). The documentation of most programs states where, and in which order it searches for configuration files. I wouldn't worry about it, though.

No shit. When I came across this blog post, I thought it was satire at first.

"Ha ha, that really nails the GNOME team's "we know better than you what you want" attitude.
... wait, it's for real!?"

That's precisely the type of nonsense I expect from GNOME developers.

I suppose KDE 3 was fairly Windows 9x out of the box, and KDE 4 is quite a bit Windows 7 out of the box, BUT KDE 4 had its design before Microsoft even released screen shots of Windows 7. If anything Windows 7 is kinda KDE out of the box.

Last I heard Mint was the most popular distro.
Ubuntu did a lot right, showed what Linux needs to become more desktop friendly, but then they got a lot of weird ideas and started forcefeeding us with them.

Arch is KISS, but it's not as easy to get a ready to use desktop system. Chakra was supposed to fix this but I think they might be having some weird ideas and they never finish anything.

OpenSUSE seemed to me a very competent distro when I tried it over a year ago.

While you're messing around you could also check out Haiku which is not Linux, it's an opensource BeOS. Very lightweight, quite different. I like it a lot but it wasn't finished enough for me to use seriously.

You can run a program from any place you feel like. note however that '.' aka 'cwd' is NOT in $PATH. so generally you want to run a program in the current dir like so: ./myprogram arguments here

Hardware access generally needs root privileges, but you can often tell 'udev' to give a device node a non root owner (user, group or both), to allow your user to access the hardware without being run as root.

Serial access is pretty easy, all (most) devices on linux are represented as files. you can open up the device's file, and start messing about with things right away. Though some hardware (like serial ports) tend to need some setup or configuration. It looks like you use the 'termios' API to play with a serial port's settings.

Hope this helped.

This one should give you a decent introduction to the Unix culture:

http://www.faqs.org/docs/artu/index.html

Specifically: All applications in Unix are, technically speaking, console applications - they all have access to stdin, stdout, and stderr, and most use at least stderr, and they can all be launched from a (virtual) terminal. In fact, most programs don't even care if they're started from an interactive shell in a terminal, a window manager, a handy-dandy launcher application, a script, a daemon, a cron job, or whatever: they'll happily do their thing, read input from stdin and pump output to stdout and stderr. GUI applications do exactly the same, except that they also use the X11 API to create and control X11 windows.

Also, C was invented on and for Unix, and its popularity made other OSes adopt at least some of Unix's features and conventions; personally, I found that many things in C (and libc) suddenly make a lot more sense when you encounter and use them on Unix.

Privileges are much simpler than on Windows, actually. They are not inherited, and owners and groups do not nest. Every file has one owner and one group, and you can adjust permissions for each of 'owner', 'group', and 'world'. And if you're root, you can do anything.

Pinguy and Linux Mint are Ubuntu based and much better than Ubuntu with Unity. Unity is more for tablets and if you're going to use a desktop, I recommend you don't go with it.

Programming is practically the same if you use a cross-platform IDE like Code::Blocks. I recommend it over VS and VC++ myself if you're going to do cross-platform work.

If you want it permanently mounted on boot, before anyone logs in, yeah you'll need to install the nfs-client or samba packages and edit fstab.

Otherwise, some filemanagers support accessing SMB/CIFS shares directly. But without it being mounted properly, most apps won't be able to access it.

The kernel is named Linux. The entire system is composed of many components, many of them developed by the GNU project for the GNU operating system, so it's arguably more correct to refer to a distro as a GNU+Linux operating system. Richard Stallman, founder of the FSF and the GNU project, among other things, would say that a "Linux" distro is really the GNU operating system running on a Linux kernel. I've decided to adopt this terminology as well.

Most of my GNU+Linux desktop experience is with Fedora. It's a pretty solid system, but it's relatively bleeding edge, so occasionally things will break or regress (I actually haven't really seen this in a couple of years though). I've never been able to successfully upgrade from one release of any distro to a newer release so I don't think it's really exceptional that [to the best of my knowledge] it doesn't work well in Fedora either [still]. As a rule, you should have backups for important data, and might as well just wipe the system clean every time a new release comes out (though you can go longer than that if you're not concerned about the latest bleeding edge software). I am the current maintainer of the Allegro 5 packages in Fedora and have done a little bit of work on the Allegro 4 packages as well.

Debian is another excellent choice, especially if you're more concerned with stability than bleeding edge. Being subscribed to the debian-security mailing list can be quite eye opening because they announce every known vulnerability in software and inform you when to upgrade packages. It can be surprising to see that some other distros aren't updating those same packages as quickly or at all in response. Ubuntu is based on Debian, but I hate what they've done with it... A complete n00b might like it, but I think it teaches bad practices and holds your hand too much. It might be good for your grandmother, but somebody that wants to do development shouldn't need the hand holding.

Arch and Gentoo offer a bit more freedom in terms of what the system is composed of and force you to become more knowledgeable faster [to succeed], but with that comes a steeper learning curve and bigger time investment. I'd probably recommend you don't bother with this until you're already comfortable in a *nix environment. You'll have enough to learn if it's as new to you as you imply. I think both also have smaller communities and that affects the age, availability, and stability of packages.

LFS (Linux From Scratch) is the ultimate 1337 experience, but it's the steepest learning curve of all. I have not achieved an LFS system yet, but it's been on my list for a while and I'd say I'm slowly building up to it.

Insert: As for desktop environments, GNOME 2 is the one that I am most familiar with, and it was pretty awesome. Unfortunately, most GNOME-based distros have moved over to GNOME 3, which I think is unanimously hated by everyone. I've never gotten used to KDE, and in general it feels bloated and clunky to me. I have been unsuccessful thus far moving to alternative desktop environments, but I think given my tastes I'll probably personally prefer a keyboard-centric, tiled window manager. I doubt this same thing would suit your immediate needs.

A few general things to keep in mind:

• "Everything is [ideally] a file";

• "Keep it simple, Stupid";

• "Do one thing and do it well";

Prefer text over binary files, unless there's a technical reason not to. Embrace the command line because it's a lot more powerful and a lot faster. It's also the only UI available for a lot of things. If you're afraid of text then you shouldn't even bother because you'll likely be whining within minutes of installation. Some may consider that a bug, but I consider it a feature.

You aren't going to learn all of this stuff over night. I've been at it for approximately 6 years and there's still a lot to learn. I love it though. The only thing that I use Windows for anymore is gaming (and j0rb), and that's only because I have to. I don't use OS X at all, but I've never tried it either so that's neither here nor there. I prefer a command line interface for everything non-graphical (i.e., gaming, graphic art, video), so I doubt OS X has anything to offer me that GNU+Linux doesn't already.