You should choose what you need. Personally I always go with 64bit at this point, as 32bit is dead in the server space. Windows Server 2008 R2 doesn’t come in a 32bit version any more, and future versions won’t either. So if you want to be able to upgrade the guests later, x64. If you don’t mind rebuilding x86.
Why are you running VMware on top of Windows? Use the bare metal VMware and cut out the overhead of Windows