You can probably go either way. It may depend on what else is on your hard drive - do you want to multi-boot another operating system on the same drive? Then you'll want to be careful. If you're not worried about something else getting trampled, I think the easiest way is for you to just start over.

It may also depend a little bit on how you made the partitions. You can make them with one tool and still change them with another tool. You don't necessarily have to go back to the first tool (say, Partition Magic) if you don't want to. But if you're starting back at the beginning, you may be more comfortable using that first tool again to make the partition bigger.

-- Ed