Hi Lisa,
(And, just as a reminder to future readers) - BitCurator is built on a 64-bit build of Ubuntu, and will run fine *natively* on any 64-bit machine (all Core 2 and newer, in particular). However, in order to run the *virtual machine* in VirtualBox, you need a machine that has the Intel VT-x extensions. You can find a list of such processors here:
http://ark.intel.com/Products/VirtualizationTechnologyIf you scroll down to the Core 2 list, you'll notice that some older Core 2 models *don't* support VT-x extensions (but there are a range of model numbers, and I'm not certain exactly which one you have).
Even on some machines that *do* have VT-x extensions, you'll have to enter the BIOS when you first boot the actual computer (not the VM), and enable "Intel Virtualization" or sometimes "VT-x", depending on the BIOS. Some manufacturers, including Lenovo and HP ship many of their machines with these turned off as an administrative measure.
So the answer is, in short, we try to support as wide a range of processors as possible. If I had to give a one-line reply to anyone thinking about working with BitCurator in-depth, I'd say "Use an Intel Core i5 or Core i7 machine". Our memory recommendations are based on performance considerations, rather than "ability to run". You can run BitCurator with as little as 512MB of RAM in a VM, but you probably won't be able to do very much.
Kam