Hardrive Partition Issues (HELP please!)

Hey all,
I have a bit of an issue here: I'm attempting to partition my hard drive for installing boot camp or another version of OS X but the system wont allow me to. First telling me to try smaller partitions, which i have, but to no avail. Next, bootcamp assistant telling me that some files could not be moved and that i should back up my system and format my hard drive. I checked my system with iDefrag (demo) and TechTool Pro 6 and it seems highly fragmented (apparently 99.50% of free space is fragmented and wont let me run volume optimisation on the startup drive). Is there anything i can do to defragment it and fix my issue without formatting as i dont have anywhere to back up my system?

Thanks in advance for any responses

Either buy the full version of iDefrag to defrag the HDD, or you could backup your system, re-install and restore from the backup and do it again!

Hope this helps

- Simon

You could image what you have with superduper or other tool. Boot from a disc with gparted (free), partition the drive. Restore image. If you want bootcamp, I would say you are limited to it's behaviors.