I am considering getting an SSD. I dont think I need more than 4GB of RAM. Would RAM really be my bottleneck? I almost always have 1GB or more free. I only use the webbrowser and maybe PPT or word. Nothing else. It shouldn't be slow just browsing the web! It's still a Core 2 Duo and I'm still only on Snow Leopard. I don't think computers should SLOWDOWN when we're still doing the same thing we were 5 years ago!
I'd add an SSD and consider upgrading to Mavericks. I know Snow Leopard certainly is friendlier to older hardware, but it seems support is being phased out, and some of the optimizations (Timer Coalescing, Memory Compression) in Mavericks actually help older hardware, too. It actually runs quite well in 4GB RAM for everyday tasks (I've got a few 2009-era MacBook Pros that have SSDs and Mavericks that are quite snappy, even compared to my much newer, faster one).