My motherboard does support SATA 2 thankfully :). Well yes, my motherboard will support DDR2 800, so I might even look at upgrading the RAM. It was quite cheap recently, not sure if it still is. Will have to have a look.
You will need SATA 2 at least to really make a difference, as modern SSDs will potentially saturate even a SATA 3 interface. Your motherboard should support SATA 2 though. I would go for some faster RAM if you can too - the Core 2 have a seperate memory controller so love faster RAM.