Hmm. I'd suggest you try dual-booting (if you aren't already). If you think you might want to switch completely but aren't sure, you could try using most of y

Hmm. I'd suggest you try dual-booting (if you aren't already). If you think you might want to switch completely but aren't sure, you could try using most of your disk for Ubuntu but keeping a partition just large enough to hold OS X just in case you change your mind.