Yes, you'll have to use something like GParted live CD though, since it's not possible (or at least very risky) to alter the size of an active partition.
EDIT: To address Scorpei's bootloader concerns you'll need you use the OEM Windows Installation disc that came with your computer. If you don't have one you'll need to borrow or *otherwise* obtain a retail copy of the Vista Installation media of the same version installed on your laptop to access the recovery console (or whatever it's called in Vista).
Or just use this command from GParted live's terminal:
Code:
dd if=/dev/zero of=/dev/xxx bs=512 count=1
where '/dev/xxx' is whatever you see in the top left corner of the GParted program.