How to shrink a windows partition to make more room for Linux?

[Brian Cluff]

> I don't know the answer to your question. I suspect however that
> qtparted may not allow altering the partition size because it detects
>  that the ntfs filesystem has been altered and is in a state that
> needs to be checked.

That has been exactly what I have found in the past that has kept me
from resizing and NTFS partition.  I've also found that the automatic
fix that it does on start doesn't always mark the volume as clean.  I've
found the best way is to manually run scandisk to make sure the volume
gets marked as clean.  Resizing a filessystem with ntfsresize always 
marks the volume as dirty, so if gpartend doesn't like to work on 
volumes marked as dirty then doing this would get you back on track.

> If that doesn't do it, I expect you'll need to delete the partition
> and re-add it, as the man page for ntfsresize says.

This was going to be my other recommendation, but I though I would add a 
little more since it's a VERY scary process.
He suggesting that you do exactly what it sounds like.  You can delete a 
partition completely and then re-add it back to the drive without any 
data loss as long as you keep a few things in mind.
Make sure that you put the start of the partition at the exact same 
place the old one was.  Make sure you take notes of the start and end 
locations of your partitions before you start.
Make sure that the end of the new partition doesn't cut off the end of 
your file system.  I usually prevent this by making the new partition 
slightly larger than the file system and then resize the file system 
again to expand into the small amount of otherwise wasted space.

Brian Cluff