Here's a guide on how to configure GRUB or LILO: http://www.gentoo.org/doc/en/gentoo-...xml#doc_chap23

Skip the emerge stuff, that's Gentoo portage system only. Once you get GURB/LILO installed, the Gentoo guide is pretty much just what you need.

(I use dualboot Win2k+Gentoo at home and dualboot WinXP+Knoppix at work )