If you do decide to do any partition resizing make sure that you have:
1) ran scandisk
2) Defragged, very important
3) Aren't trying to make a new partition greater than about 70% of your current free space
Personally I would just pick up a small drive. All you will need for linux is 10 GB TOPS. Probably only 4 or 5 at first

The install will be 2 GB MAX and that will include almost all the software you will need to do anything.
Jkrohn