Re: change partition
IF you're running Win7 (or Vista), do NOT use the Ubuntu installer, or any Linux utility to shrink the Windows OS partition. These Windows versions are very sensitive to changes from "outside" (i.e., Linux) and can easily become corrupted as a result. If that happens, you won't be able to boot into Windows anymore.
Instead, use the Win7 Disk Management utility to shrink the OS partition. Once you have done that, reboot into Win7 a couple of times to let it make adjustments.
Also, you won't be able to make changes to your Linux partitions while you're running Ubuntu from the hard drive because they will be in use. Instead, you will have to boot from an Ubuntu LiveCD or LiveUSB, launch GParted, and make the changes from there.
Ubuntu 15.04 Mate, Mint 17.1; MS Win 8.1, Win10 TP.
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