Starship Troopers (which isn't very good, by the way) is an old game from 1997, which is why your friend suggested using XP instead of the more recent Vista. You might even want to try Windows 98.
If your friend thinks it will work under XP in a VM and you're prepared to spend the money on a new operating system just for this game, then VirtualBox is the best FREE Virtual Machine software. VirtualBox lets you install another operating system (like XP or 98) inside Vista, so XP or 98 runs in a window that can be maximized to fill the screen.
Only the more expensive Professional and Ultimate versions of Windows 7 allows Virtual XP, and only if you have a particular type of CPU, so might not be suitable.
You don't need to send me a PM after each reply. I can see your posts in this thread. :smile: