Format Mac HD from Windows XP (bootcamp)

I cant edit the title, but i meant DEFRAG MAC HD FROM WINDOWS XP (bootcamp) not FORMAT

Okay, we all know that MAC OS does not come with a defragging utility. Some may say, its built in, or it doesn't need one. Bottom line is, my girlfriends Hard drive, needs to be Defragged.

I tried to use iDefrag, and it was doing a great job, and then it was like, sorry couldn't move some files because they were in use, or just plain old couldn't move them, cause there wasn't enough room to.

Unlike the windows one, where it first calculates, whether or not it will be successful with the amount of remaining space. iDefrag doesn't.

So I managed to partition the 110gb hard drive into 100gb for the mac, and 10gb for windows.

Now my question is, because her mac Hard drive is really fragmented and running really slow, compared to how it was when she first got it, non-fragmented and clean, is it possible to defrag the Macintosh section of the harddrive from Windows XP. Has anyone tried this before?