Anybody who has used a computer running any version of Windows will probably be aware of the oft-quoted piece of tech-savvy wisdom that says you should clean out the Registry every now and then. It was strongly believed that a "clean" Windows Registry would result in significant performance gains for your PC. Because of this, a number of tools were produced by sofware manufacturers to address the registry issue, many of them promising miraculous improvements in your PC's speed. I was never too sure about this, but lacking any convincing proof either way I tended to go along with the prevailing view.
Well, it turns out that the sceptics were right after all - you needn't bother doing any repairing of your registry at all. You may effect some minor improvement in your PC's performance (perhaps 5% or so), but it is also possible that you could cause serious corruption in the registry resulting in catastrophic failure of your PC. Several articles have been published recently about this, on respectable web sites such as Gizmos's Freeware and Life Hacker. Ed Bott, a well known technical journalist who has been writing about IT-related issues for many years (see his blog), had this to say on the subject:
Don't run registry cleaner programs, period. I won't go so far as to call them snake oil, but what possible performance benefits can you get from "cleaning up" unneeded registry entries and eliminating a few stray DLL files?
So the current view is that unless you know you have some major registry problems, you should NOT perform any "cleaning" of the registry at all ; the danger of wrecking it completely far outweighs the small gains you might achieve. Simply put - don't bother. Just leave things as they are and you'll almost certainly be better off.