External hard drive recommendations?

I'm looking at purchasing a new external hard drive after experience compatibility issues with my old AcomData hard drive after trying to connect it to my new iMac (I had to connect it to my laptop that was running an older version of Leopard, access the iMac via my network and drag the files through the laptop to the iMac). Is the Apple Time Machine the way to go? Or would you recommend something else instead?

Edit: I missed the completely obvious thread above this; please lock/delete this