How to quickly start Programs like "regedit.exe" from the Windows 7 search bar using substring matching?

Solution 1:

You can enhance the capabilities of Windows 7 Search if you install a little freeware app called Classic Shell.

Then the Search functionality will not only list "regedit.exe" for substrings like "reg", it will also remember over time which option you launched most often for each search string and after a while you will see that option preselected by default when you type the same search string again. (It's extremely simple to implement, you just have to save some counters and do some comparisons, but it wasn't implemented)