There are prior discussions on this. It's not trivial so I'll suggest you get an estimate from an Apple Store on how much for them to do this for you.
Again, this question has prior answers but I can't guess what stopped you.
https://www.google.com/#q=increase+space+on+apple+windows+bootcamp
There is a really big step one must do before attempting this. BACKUP THE ENTIRE DRIVE. Superduper ( http://www.shirt-pocket.com/SuperDuper/SuperDuperDescription.html ) can copy the entire drive so you can recover from mistakes.
So, originally I had a friend partition a laptop I bought to have split the HD space so I could have both a Mac and Windows OS. I've now discovered I really don't use the Mac side, and I'm running out of space for the windows side so I want to:
A: Mirror the Windows partition so I don't have to reinstall all my programs.
B. reformat the laptop so the entire drive has the Window's OS.
Thanks in advance :-D

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