dual boot with vista ?

so i have vista ultimate here bought it for a computer build and the people then decided they just wanted XP so im thinking of making a dual boot with vista on my pc
currently specs are AMD dual core 5000 @ 2750mhz each core
2GB of RAM gonna be 4GB as soon as it arrives
2x 250GB HDD
ATi 3870 and putting another one in when it arrives.
OS : XP pro
computer is completely multi taskable use it for Office, music (in a band), and games usully CoD4, Crysis, flight simulator x,command and conquer 3

is it worth it ?
are all the problems sorted with it ?
and finally how do i do it
thanks guys

 

Since XP is already on, just make a say 50 GB min partition and boot from the Vista DVD and install to the newly created partition. A dual boot menu will be created automatically.