Need Registry Advice

I installed CA Security Suite & got this error (PPCTL.dll is damaged and could not be repaired! This may be due to CA Anti-Spyware being run from an account that has insufficient permissions to do the repair, or the file being in use by another application that also uses ppctl.dll.). I went to their site & it says to go to the registry
1. (click on Start>Run>type regedit or reged32 and click ok)
2. Scroll to the key HKEY_LOCAL_MACHINE/SOFTWARE/Classes/
3. Right click on the Classes folder
4. Choose Permissions and click Advanced
5. Add the user's name to the permissions list and ensure the user has permissions to both this key and sub keys
6. You can perform the steps for this registry key HKEY_CLASSES_ROOT/PPCTL and set permissions here also

They had some screen captures showing the screens, then said that (Once you perform the steps given above, it should resolve the problem with the PPCTL.dll damaged issue. If I do those changes how do I get out of the registry?

I had always been told not to mess with the registry, so I've very hisitant to mess with it. Also, I had problems with my PC last year & took it to a local repair shop & the guy took off the sign-in at Start Up, so I don't know what 'user's name' to use as the permissions name; so I'm kinda at a loss what to do, because I know if I mess up the registry, this pc won't run.

If you want to dmail me or email me off site, please feel free to do so at quiltsnhosta @ yahoo.com with the spaces removed.
TIA,
Jan in Central Illinois