Thanks for showing some interest Lumbee! The AltOS Abode is a great place to ask any Linux/UNIX questions you might have.
Regarding your questions, you can do almost anything in Linux as you can in Windows or MacOS. All of the general use things like browsing the web, burning a CD, writing a paper, managing contacts, spreasheets, making a presentation, some basic gaming, photo editing, and so much more are all covered in a normal Linux install. The only thing you'll have trouble with is when you want to start doing some really niche items like working with Visio products, trying to use Photoshop, or playing today's hottest gaming titles.
There are different "flavors" of Linux available. Some are meant for the seasoned pro, some are meant for the complete n00b, and every where in between. There are also specialty flavors for embedded hardware, a small variety of cellular phones. netbooks, and such. These flavors are called Distributions, or distros for short. There a lots of great sources on the net for learning about Linux, no matter what use you're looking to use it for.
Ubuntu is a great distro for someone like yourself that's just getting their feet wet. It has a good and large userbase, it's very stable, and quite easy to use. Some distros like PCLinuxOS and LinuxMint focus even more on ease-of-use, but Ubuntu is one of the best compromises on all fronts.
Some of my favorite links for learning more about Linux are
I also can't complete this type of post with out a shameless plug to my own Linux blog.
Hope this helps you out some. If you have any more questions, be sure ask.