Instead of plunking down the money for Partition Magic or Acronis, just use the open source project Gparted. The trick is you don't do it from windows. You boot linux and make the changes. You can download a linux ''live CD'' that boots directly to the partion manager. It is incredibly simple, just like using one of these windows based tools. No muss no fuss, you don't even know it's linux. Before you start, move all your data from the larger partition to a backup, delete the partition then resize the smaller partition with the OS on it to use the whole disk. Remove the CD, reboot into windows and copy your data onto the drive. Very easy. Plus this is a nice tool for making a partition if you so desire.
It goes without saying that you should back everything up before you start regardless of what tool you use.
Help, my PC with Windows 10 won't shut down properly
Since upgrading to Windows 10 my computer won't shut down properly. I use the menu button shutdown and the screen goes blank, but the system does not fully shut down. The only way to get it to shut down is to hold the physical power button down till it shuts down. Any suggestions?