Moving program files or user to E:/

Moving the files from the "Program Files" directory will definitely not work. Most programs such as Office and VS have registry files also associated with them, which will be rendered completely useless if you move files.

As you said your drive is just 40GB, I presume you haven't installed many programs on your OS. If you have the time, you could uninstall most of the programs and reinstall them into your E:\ drive. Even if you do this, your subsequent program installations should be done into E: drive or you might still run out of HD space.

For the program files, there is always a risk involved: There are LOTS of programs out there, that have C: hardcoded. This sometimes poses a risk also for user profiles.

To work around this, I typically use junctions and mount another partition on the corresponding directories.