It appears that it's probably the win2k boot loader that is showing up when you boot up. To see if that is correct, you'll have to take a look at the boot.ini
file in win2k. The file is hidden so you'll have to unhide it. Go here
and then scroll down to ' Windows2000 Boot Procedure ' and follow the directions to unhide it. This page also tells you how to add linux to the win2k boot loader. After you unhide the file, load it into text editor and see if it has a line that has ' xp ' in it. If it does, then it's win2k's boot loader that's starting up.
Like I said before, you can add linux to win2k's boot loader. Did you make a boot disk when you installed linux? You need to get into linux to be able to add it to win2k's boot loader. If you can get back into linux, you can follow the instructions on the page I gave you and add linux to win2k's boot loader.