Vista won't show up on dual boot list

I have an old laptop I used for gaming which has vista on it, but unfortunately I couldn't get some games to work on it. Warcraft I, II and the like. I had made two partitions on it a while ago so I could have Vista and XP on it but I must've seen something shiny and walked away from it because XP wasn't loaded onto it yet. I got XP loaded onto it and now it only boots to XP. It doesn't give me the option to go in to Vista.

I'm curious if anybody else has done this. I realize now I should've done a virtual machine with xp from vista, so if I can find my vista disk I might just wipe the whole thing and start over.