Non VIP help request

Hey, I couldnt find a section for general tech help so I thought I would put it in here, if thereis one can you please move it and mention me

Right, well basically I have a Dell dimension computer running xp home, and recently I bought another sata hard drive and installed win7 onto it, is there a way j could have an option on startup askiing which hard drive I want to boot from? I can't format the xp hard drive as it has my sisters stuff on it, I'm using two separate hard drives and not just one partitioned into twos

Thanks in advance