Using CCleaner program's Registry Error Scan, missing dll's were listed, and it deleted these "error's" to "Fix" them.
Could they have been important to overall pc function, or slow it down, etc? I have no XP Installation CD and need to download something to search for problems. (Trusted ones and Free ones, hopefully.)
Have I caused problems with my XP system? Or compromised it, in the CCleaner use??
No,, you haven't. CCleaner is one of the safer Registry cleaners, skimming over the top and removing only the clutter. If it described something as missing it really should say the associated files were missing and those .dll files could safely be removed.