In reply to Rodrigo.

I think if you don't have huge data or programs that require lots of memory, then the 32-bit version is fine.

However, note that currently SAS 9.4 (the most recent version of SAS) has only a 64-bit version, and not a 32-bit version. A 32-bit release is under consideration right now, but in the meantime you can use the x86 (32-bit) version of SAS 9.3 for Windows on a 32-bit or 64-bit OS.