Many people tell me not want to lose your Windows XP because they already have well configured and are ready ...
Enconces the solution is dual boot ...
1) Partition your disk using: Gparted or Partition Magic or Acronis two NTFS partitions leaving at least 10 GB for Windows Vista.
2) Install Windows Vista on the new partition.
3) Then choose your operating system at boot time, facilitated!
Here the source of information:
http://lifehacker.com/software/top/windows-vista-beta-how-to-dual-boot-windows-xp-and-windows-vista-179906. php
Luck
Cnorte.net
