I think Maxtor and Western Digital are both quite good. I've also not had any problems using an internal drive installed in an external box kit.
Depending on your needs, you also might want to consider getting 2 drives instead of one big one.That way, you can have two copies of any important information (eg. I've got my MP3 collection backed up as well as my huge AVI home video files.)
I just realized that, counting laptops, the desktop and 2 external drives, I've got over a terrabyte of storage at home.