After re doing my desktop with a SSD drive i wanted to boost up my i5 laptop so i removed the stock 500gb sata HD and replaced it with a 60gb Intel 330 SSD and everything went great. If you want to give your laptop a nice speed boost at a somewhat low cost i would go with a SSD drive.
The install is really easy. It is just 4 screws and doing a quick swap of the drives. I would suggest a fresh install of windows 7 vs cloning the drive over to the new SSD drive.