As the name implies it modifies your Registry. The first think you should do is backup your registry, and create a new restore point. This is your fail safe if things should go very bad. It does not take very many registry changes to to render your operating system unusable. ERUNT
will create a backup of your registry, or you can do it manually. Whatever you do BACKUP your registry.
If you computer is not being adversely affected by these so called problems you would be better off leaving them like they are. IMHO
I am sure others will weight in on this topic thought.