Adding to what Fred said, I just recently purchased a desktop Seagate 80GB SATA drive. It is rated for both 150 and 300 speeds. My motherboard will run the 150, but not the 300. Seagate has a tiny jumper that comes already installed that limits the drive to 150. I just plugged it in and loaded Mint. It only took a minute. Now, when I do eventually move this drive to another machine that has 300 support, all I have to do it remove that tiny jumper. Even though I cannot use that 300 speed right now, I have that future capability built-in.
I think I paid $44 for that drive (including shipping). I have not priced the laptop models, but with drive prices as they currently are, you will get a deal no matter which way you go.