I'm sure you'll have a lot of people telling you to go with an Seagate, but I don't trust them by a long shot. They used to be really reputable back in the day as far as I remember, but they are now Maxtor, essentially, and I loathe Maxtor.
In fact, I had bought a portable Seagate HD (500 gig firewire) last year, and it is turned into a paperweight about 3 months after the purchase. Wasn't readable or mountable at all. And trying to get in touch with customer service was just impossible. I now stay away from them, no matter how good of a review their products get on here.
On the other hand, in my entire life I've had nothing but positive experiences with Western Digital drives. Both internal and external. I currently have a several year old 500 gig MyBook (only USB 2) and it works great. I too am going to replace my 13" MBP's HD with an upgrade, and will likely be a WD.
But instead of telling you which one etc.. I'm going to do you another favor. There's a search button in the top menu. Hit it. Enter into the search box: "hard drive upgrade", and you shall find tons of threads with everything you're looking for. Sometimes, the search feature really does work.
Doug