Dual booting isn't going to slow your system down because you can only use
one operating system at a time, at boot up you either boot to XP or Vista.
You do, however, need two partitions, one for Vista and one for XP. You can
even install XP on a system that already has Vista installed. See this link
on my website.
http://vistasupport.mvps.org/install_windows_xp_on_machine_running_vista.htm
An alternative is to use virtual machine software, although you do need to
have enough memory and this option may slow you down somewhat.
--
John Barnett MVP
Associate Expert
Windows - Shell/User
Web:
http://xphelpandsupport.mvps.org
Web:
http://vistasupport.mvps.org
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