Is Registry Defrag Useful?

I've used many so-called system optimizers and have found many of them to include a registry cleaner and a registry defrag. There have been times after uninstalling a program that there are many references left behind by the program that are found by the registry scanner. Junk that I would like to see removed. It's more piece of mind knowing that I removed unwanted entries. I'm not being very savvy as far as what these entries can do if left behind. Can they trigger malware? Can they access a web site without my knowledge? I just feel better removing them. Of course a registry scanner won't get everthing.
My question, I guess, after removing many entries in a situation like the one above, is it useful to defrag the registry? I honestly don't see any performance improvements in the few system optimizers that I have used.

Any thoughts are appreciated,
James

I agree with the previous poster - leave registry maintenance to Win7 which is better at it than previous OS. I would also steer clear of registry cleaners, they can cause more harm than good and will not improve performance.

After CCleaner's aggressive registry cleaner screwed up my grandson's computer recently my advice would be to forget tampering with the registry.

As previous posters have said, Windows 7 does a pretty good job of taking care of business.

If it ain't broke, don't fix it. :)

JamesJ said:

It's more piece of mind knowing that I removed unwanted entries.

I just feel better removing them.

Deal with why removing unwanted entries should affect your "piece of mind" or make you feel better. Those are emotions.

{For the umpteenth time}

IMHO.

Current accepted wisdom with Win 7 is to NOT use a cleaner.

If you ever think your Registry needs to be cleaned, repaired, boosted, tuned-up, cured, tweaked, fixed, or optimized it shouldn't.

In other words, injudicious use of "Registry cleaners" CAN cause problems.

IMO - there is no reliable way for a third party program to know whether any particular key is invalid, redundant or neither.
Some registry cleaners may not know for sure whether a key is still being used by Windows or what detrimental effects removing it may have.
This has led to examples of registry cleaners causing loss of functionality and/or system instability.

FYI
Do I need a Registry Cleaner? | What the Tech