I have Ubuntu 8.10 installed with Wubi, and I would like to update to 9.04. However, my Wubi install is giving me some problems with both Windows and Ubuntu, so I want to back up my Ubuntu data and transfer it from 8.10 to 9.04. What is the easiest and safest way to partition the drive?

Also, if it matters, I have both a C and D drive. Does this mean that I can make an ISO of 9.04 and just install it into that? If so, how do I do that?