The sandbox can run on a 32bit OS, but it does require a processor that supports virtualization (and/or 64bit?). If you go to the VMware Knowlege Base article listed they have a tool that you can download that will let you know if your system is compatible. Also, you can read up more on the Intel site about virtualization, they also include a tool and a link to a page that lists compatible processors.
In some cases this is a feature that you can turn off or on. Here's a screenshot of it in the BIOS settings.
In short, this does look like a processor issue, not a 32 vs 64 issue. Even if your processor was compatible, trying to run a VM on 2 GB of ram would be painful at best. My 4 GB machine becomes unbearable to work with running the sandbox.