Fragmented Harddrive, Bootcamp.

I have an iMac (late 2009) with a 500gb hard drive. When i was trying to create a partition for bootcamp I ran into an error because of fragmentation. After deleting almost 200gbs of info i now have about 275gb free on the hd. I bought iDefrag and have ran the Full Defrag and the Compact algorithims. After all this i still run into the same error telling me to restore to a Max OSX (Journaled). I would like to avoid all restoration of hard drive methods if posible (Cloning harddrive, restoring to a backup, ect.). I only want between a 100 and 50 gb partition.

That is a picture of the bitmap at the bottom of the iDefrag for my harddrive. Im confused because i obviously have more that 100 gb avalible.

Thanks for any help.