Best way to resize OsX/Win partitions

I assume the Windows partition is a Boot Camp partition, correct?

I don't know of a way to resize it without using the Boot Camp utility to remove it and then recreate it at the new size, which obviously means you'd have to re-install windows in some way.

What might help is to use a paid app called WinClone: http://twocanoes.com/winclone/. Using that, I think you'd be able to clone your Windows system to an image file, adjust the partition with Boot Camp Assistant, and restore the Windows system with WinClone.

It may depend upon the version of OS X you're running, and the version of Windows.

I successfully used Winclone to save my Boot Camp partition (XP) during an OS X upgrade that involved repartitioning my main drive, and then to restore it afterward to a larger partition. I was a bit nervous, but it worked. However, I'm not sure if it'll work to restore Windows to a smaller partition -- you'd have to check into that first.

I'd make sure I was very confident in my backups before doing anything like this.

 

I've used winclone to resize my windows partition -- both smaller and larger.
It's a multistep process, but well documented.
I was specifically working with Mountain Lion and Window 7.
You do want to be confident of your backups before starting.