Kwack, yes it can be done.
Move the data off of the first partition. Make a Windows 7 backup image of the System and Windows 7 drives which you save externally in case you need to start over, as moving operations can fail. Or at least back up the data.
Download free Partition Wizard bootable and burn to CD: http://www.partitionwizard.com/download.html
Boot into PW right click D:Games and Delete. Now right click 100mb System Reserved and Delete or Resize/move, if moving drag the partition over snugly against the left border.
Now right click C: Windows 7 and Resize/Move, dragging its left border over against the System Reserved or left border, resize C: as desired.
Next, if you deleted Sys Reserved partition, rightclick C: and Modify: Set Active., Apply all steps.
Now boot into the Windows 7 DVD Repair console and run Startup Repair 3 separate times as it will need to repair or rewrite the MBR to System Reserved or Windows 7 Partition.