How to Uninstall Windows XP, after a Windows Vista Install (I dont want to OS on PC)

I bought my copy of Windows Vista Home Premium yesterday, during installation, It said its not able to update from XP, and that it needs to do a Fresh install, when I boot up my PC now, It keeps asking me to choose what I want to Boot, XP or Vista, is there a way I can delete XP, I want to only have Vista on here now?

Regards

Thanks for the Help.

 

honestly if you don't have anything important on vista yet the easiest thing might to just reinstall vista and just format the whole hard drive during setup.