For quite a while now I've been using BootNG's demo disk to resize NTFS partions.
It comes at no cost, and works pretty well.
But I recently discovered that there is a GParted Live CD which can both boot your machine, and run the same GParted that you run in Linux.
Why would I choose one over the other? Well, first I had to go find Gparted Live CD, because BootNG would not work on a Dell D620 I was working with the other day. Second, GParted will handle almost any type of partition you can think of for a PC.
And it is completely open source, released under the GPL which is great because you don't need to worry about some comercial entity deciding to pull the plug on their free product. (you only need to worry about the project dying off!)
update - this thing does even more!