Ok, I'm new to Unix/Linux, so please have a little patience with me. I want to move away from Windows because I think Bill Gates can be a real @#$!%*& sometimes.
Ok, I've noticed from playing with BSD, Ubuntu, and Debian that you must install programs manually with them. But how do I do this? Sometimes I can get an app on CD for Unix or Linux, but it's just a bunch of .tars or .gzs, compressed formats I know nothing about. Other times it's just source code that I don't know how to compile. (Sorry, I'm a nub to programming/compiling, too.) What the heck am I supposed to do?
Basically, and not to sound rude, RTFM. tar and tar.gz are both just zipped formats as you already know, but they should have a readme either in the archive, in the folder of the archive, or on the website you got it from. The file name might even give away what distro it is intended for, if you run that version it should be documented how to install by your distro. If it is containing a binary file, a directory listing should show it, and then you just need to be in that folder and run ./[file]
You'll only VERY rarely need to install something that you download yourself or find on a CD, and you should be suspicious about anyone that tells you that you have to as you're circumventing a whole bunch of security features. Each disto has a method of installing software that it already knows about (and it knows about practically everything that is out there in the case of Debian/Ubuntu), and in their case it is done through a GUI, so you don't need to use a command prompt even.
Google is your friend and so are the forums for whatever distro you settle with, first thing to realize is that any newbie question has already been asked thousands upon thousands of times, so the answer is almost always out there.
I suggest you sell it on eBay then do some research to find something that explicitly is supported by Linux. Those Netgear ones are just bad news, if it is in good condition get rid of it while it still has value second hand. Sorry I can't help suggest one TO buy, but can help with what NOT to buy. If you're on a laptop, maybe look for a mini PCI card, if you're on a desktop a normal card that you physically install. You should be able to find something with native drivers that doesn't rely on ndiswrapper or proprietary firmware. Your connection will be a lot more reliable and it will save you a LOT of headaches down the road.