replacement HDD question

I have a macbook pro 4,1 (early 2008, non-unibody) with the stock 200GB 5400 rpm hard drive. It's a 1.5Gb/s linkspeed, but I read that the 3Gb/s HDD's are backwards compatible. Do I need to purchase any adapters for this?

Also, I don't know which drive to get, because on the Newegg customer feedback, all the top 7200rpm drives seem to be having problems. I'm trying to decide between the WD Scorpio Black 750GB and the Samsung Spinpoint MP4 640GB. The WD seems to have a firmware problem with OSX, while the Samsung supposedly struggles with bad blocks developing. I've never bought a hard drive before, so I want to make sure I get the right one.

Note: I would love to get an SSD, but I can't afford it.

 

Thanks for the quick reply! I don't see in my system profiler if I have the SMS feature. Does that mean I won't need to disable the SMS of the Seagate?