If the programs etc. you've lost are still installed on your PC and you've just lost the values so that some pieces of the program aren't showing up on your PC, importing the appropriate values should help, so long as .dlls' etc are still on your computer.
You should be able to use windows' own registry editor for momst things, although the basic editor is slightly restricted in what it will allow you to do. Try using regedt32 next time.
I'd also recommend using UltraEdit, it can be used for all sorts of things including editing the registry and hex translations.
UEStudio / UltraEdit / UltraCompare / UltraSentry - Text Editor, HTML Editor, HEX Editor, PHP Editor - News
Regards
Martin