Changing the default installation directory in Windows 7 through registry changes

I have an SSD as my OS drive, and a much larger 1TB HDD for my general purpose drive. I prefer to keep all games/non-vital programs on this drive (the HDD), but some programs force themselves into the C:\ drive instead.

I've read up on ways to change the default installation directory using regedit. Has anyone else with a SSD done/recommend this?