If you choose Flash note that to boot from a USB drive, your computer's motherboard and BIOS must support USB booting.
Would I not have that same problem from a disk drive? I guess I should have made it more clear I meant an external disk drive. Like I said, I want to be able to take it with me. Also, how much of a problem is that? I mean, do many MB nowadays not have that support? (I do already know mine does, just curious about odds)