I have those exact specs with my 2009 MacBook Pro. (See my signature.) Your mom's MacBook is basically my MacBook Pro with FireWire removed and a plastic shell.
It runs pretty well with SSD and 8 GB RAM. It also runs pretty well with SSD and 4 GB RAM.
It runs poorly with 2 GB RAM.
It runs poorly with hard drive.
If you do upgrade the memory, look for the EXACT specs including both the clock speed and the CAS delay timings. Some of the companies like Corsair I believe will actually sell Mac-specific RAM, which is just their regular RAM, but which has been spec'd exactly to match what is needed is Macs. You end up paying a few bucks more for the peace of mind. OTOH, if you get the wrong RAM that seems to match up but don't know the CAS timings, it may not work at all. Places like Crucial will provide the exact RAM for that specific model, but their RAM is pricey. Furthermore, they won't sell you 8 GB RAM for that model, since Apple only officially supported 4 GB. However, 8 GB should work unofficially.