XP 64bit vs XP 32bit

64-bit has been tested to run 32-bit apps approx 33% faster than your conventional 32-bit OS. Now with that being said, unless the software you have is written to be supported by a 64-bit OS, they will not install. In your case, I would DEFINATELY setup you system for dual boot in case you have issues installing your software. I ran XPP-64-bit for two weeks but at that time, i had issues with drivers for NIC, Sound and video. So I went back to 32-bit. Just make sure the software you want to install is supported before you make a whole lot of work for yourself.