Macbook Pro running slow

HELP, my Macbook Pro is getting slow and I dont like that. I hope someone can help me to get the speed back.

Mac OS X Lion

Ver 10.7.2

CPU 2.26 intel Core 2

Ram 8gb

HDD 250 and I have 165gb left

Its about 2yr old

I have ran repair disk and that has done nothing. If you need more info please let me know.

Thanks,

Jason