windows xp right?
make sure you have an administrator password (just in case)
remove that boot sector virus protection
that should work but I'm pretty sure it will not recognize your windows on /dev/hda you'll need to add something like this
title Windows 2000
title can be whatever you want
rootnoverify just says don't verify directory of hd0,0 (primary master, first primary partition)
chainloader hands control off to boot.ini