For an internal drive I like the Seagate Barracuda 7200 RPM SATA (5 year warranty) or the Maxtor DiamondMax 10 7200 RPM
Watch out for the lowest price advertisers. Those will be OEM's or "pulls" with zero or one year manufacturer's warranty. Your REALLY WANT the full warranty, 'cause every hard drive in the world will fail eventually.
personally i like hitachi drives. they have huge drives (now at 500gb) apple uses them and i mean what the heck 250gb today 500 tomarrow. the more you have the better really, future proof! however they are expensive
I would go with the LaCie I have the tripple interface and I love it the firewire 800 is great when I am transfering stuff from my friends powermac I am on windows right now but am going to be getting a powerbook for college in a few weeks and let me say if you do things like photoshop or audio mixing its great it will give you a nice speed boost if you have the files on the Lacie and the program on the main system drive. I have my 200GB Lacie and I love it and I think you will too plus they are built like tanks.
I use this Simpletech external HD; it has both Firewire & USB 2.0.
I use it primarily for intermittent backup of files & I've been happy with it thus far.
Very unscientific, single-user experience with a duration of only months, but I can say that I haven't been unhappy!