Moving MP3 library to external drive

Hi guys. I want to know what are the directory's/files that I need to move to my external hard drive in order to not have to re-analyze all the peaks and BPM? Same thing with collections/playlists/etc. I'm guessing I'll need to re-point the software somehow as well. I have been testing from a laptop to desktop streaming the songs over my home network. I want to know move my (200+ gigs) of tracks over to external so that I can take it portable with me on laptop with out desktop.
Thanks!
Thanks!