Yeah, the problem with a 32-bit program, which I am assume you are using, you can only run 4GBs of RAM and only ~ 3.2 of that is "seen" by the OS. And, given that VMs love memory, that would be the only issue. Server 2K would probably give you a nice application TS with no license issues if using XP.
But, RWW is the way to go at least short term. Just the OWA itself is worth it.
