hard drive performance question

I have a mac mini with 4 gigs of ram 1.86 C2D and a 80gig 5400 RPM sata harddrive


should I replace the 5400 rpm 80 gig with a 200 gig 7200 RPM laptop drive or should I connect my brand new western digital SE16 750 gig harddrive via firewire 400 and boot OS 10.5 of that


so... laptop internal or desktop external???


I'm looking for the faster performer

i'm not hard drive expert but i'm fairly sure that sata is quicker that most if not all external ports i'd recommend getting a internal for os, programs etc. (the things you need the speed for) and then putting your music etc on the external(the files which are not effected by slower read/write rates).