Keyboard keys not responding

Hi everyone

I just recently got a white Macbook 2007 and after I installed snow leopard on it I realised that the I,K and LEFT,RIGHT,UP,DOWN keys were not working and so I installed leopard on it and still had the same problem I booted into safe mode on both but still no luck and this morning the Z key stop working I turned of mouses keys and that still did not work.

Does this mean a trip to the Apple store because its only a 2007 model is it really worth fixing ?

Thanks Bananaboy