My preference would be Parallels. The setup does all the
work for you and it supports more than BootCamp.
With BootCamp, you have to restart into windows.
With Parallels, you can run Windows along side of the Mac
OS.
BootCamp, you have to use WindowsXPSP2, Vista later
probably.
Parallels, you can install any version of Windows, Linix,
etc.