Installing Games on Vista Ultimate x64

I was just wondering, If I have a x64 based PC running Windows Vista Ultimate 64 bit version, should I install all my games in the Program Files folder or in the Program Files (x86) folder, I know that the x86 program files folder is meant for 32 bit applications, does it make a difference when you install games in the x64 program files folder rather than the x86 folder? Would uninstalling and then reinstalling the games onto the x64 program files folder increase the performance of the game at all or does it make a difference at all since my PC is running Vista Ultimate 64bit anyway.


My PC Specifications:
x64 based system
OS: Windows Vista Ultimate 64bit
Processor: Intel Core 2 Quad Q9550 Quad-Core 2.83GHz
Fan: Cooler Master Hyper TX X2
Motherboard: ASUS P5N-T Deluxe NVIDIA 780i
Memory: Corsair XMS2 Dominator 4GB (2x2GB) DDR2 1066MHz
Storage: Seagate 1TB (2x500GB) SATA 32MB cache
Graphics: 2 x NVIDIA GeForce 9800GTX+ 512MB (SLI)
Audio: Creative Sound Blaster X-Fi Titanium
Optical: Pioneer 20x DVD-writer SATA
Chassis: Cooler Master Cosmos 1000
Power Supply: PC Power & Cooling Silencer 750W Quad
Keyboard: Razer Lycosa
Mouse: Ikari Steelseries

Most games are 32bit except for crysis which is both.