Most every Distro works fine. Very stable. Give Mandrake a try.
You can find install CD's easily from links provided by
linuxiso.org. You can also find linux-on-a-cd distros like Knoppix. Using those you can run a OS from a CD without having to install anything. Then later you can install a OS if you like it.
Doing a search in google will provide plenty of information. Like
linux microsoft application alternatives. Think of search engines like google as your online help resource, much more usefull then anything I've ever seen for any other major peice of software like a OS.
You have Mozilla for a internet browser, but you also have Galeon, Netscape, Opera, Ephiny, Konquerer, and a whole host of other browsers to choose from.
For office applications you have Openoffice.org or Staroffice, which are entire office suites ment to replicate and improve on the functioning aviable from MS office, but they can be had at little to no charge in price. Then you have office suites made up of individaul programs like abiword, that are provided by GNOME or KDE desktop enviroments. These are very good.
You can find most everything you'd ever use in Windows installed by default in most every linux distro.