cannot upgrade vista basic to business

ok... i'm a n00b.. i have a pc with preinstalled vista home basic. and i have vista business installer dvd and i'm trying to upgrade my vista basic to business. the problem is when i load the dvd, the upgrade option is being disabled. how can i solve this?

Have you tried booting from the CD? You might need to change your boot menu on startup.

i tried that, but it says my device driver are not found.