Check out
this previous forum post for information
As well, check out
Distrowatch.com and read some reviews on different distributions. On the right side of the page you'll see a list of the top distributions (according to page hits), check out each one of those and read reviews on them to see if they're suitable for you or not. You definitly need to do a bit of research before diving in. It's almost like buying a car

If you have any specific questions, let us know.