If what you care about is game performance, then just go with Home Premium 32-bit. You don't need the expensive version, to get that. The main difference between a 32-bit OS and a 64-bit OS, is that the 64-bit OS is capable of allocating much larger files, and more than 3.5GB of RAM. Where as the 32-bit cannot. But you don't need 64-bit as of now, because the majority of software is still 32-bit. And you're only getting 2GB of RAM.