I have installed a Kingston 120GB V+200 SSD into my late 2008 model and it works just fine (not at the sata3 speed but much faster than the stock hard drive).
I also bought a optical drive bracket for the old drive which I now use as a storage area.
Whilst I had the laptop open I also cleaned out the fans as it was getting hot during normal use.
All of this has made my mac like new again! Well worth the effort!!