Can't Delete Old Updates (winsxs Folder)

Hello, I used to be able to access an option in the Disk Cleanup tool (cleanmgr.exe) to delete old Updates files. Now, the tool merely scans for updates but does not display the appropriate checkbox. My winsxs folder is growing out of control. Installing a couple of recent updates (like 1GB of Office updates and a new 400MB driver package for my video card) is slowly eating away the remainder...