. . and Pro has a bunch of mobile computing stuff. Other than that, and a $50 to $100 price difference, they are pretty much the same.

If your computer wasn't built for Windows XP (eXtreme Pain), then you shouldn't try to run Windows XP on it unless you are very adventurous and your computer is at least 500-MHz with 128-Meg of RAM. 1-GHz+ and 256-Megs is more comfortable.

Linux (a more user oriented version of Unix) is becoming the successor to Windows in a growing number of company environments. Cheap computers like WalMart's may or may not start the same trend in home computers.