If you intend to increase the memory to 4 Gig or more in the future then install 64 bit Windows, If you intend to stick with 2 Gig for the foreseeable future then install the 32 bit version. The 64 bit version of Windows is slightly faster than 32 bit version but uses more memory which would make it slow with only 2 Gig of memory. 32 bit Windows is more compatible with older programs and can use unsigned drivers.