Registry errors

I currently have Norton Security installed. First, I would like to know the difference between Norton Security and Norton Internet Security, which is the program I thought I was buying. They are apparently different because when I check to see what Symantec programs I have licenses for it lists both programs and shows my Norton Security as active and the other one due for renewal.

I have had many issues since installing Norton Security--PC running very slow, hiccups in Microsoft Outlook, clicking to open an email and the PC jumping back and forth to different screens etc. Norton support helped and set the proper defaults but I am still having major issues with my system.

I suspect possible registry errors and don't know if my Norton Security program checks for these. I thought I was buying a complete program to protect the PC but it appears that Symantec has these sectioned off so you have to buy several programs to take care of a plethora of issues. So, my question is two-fold; does Norton Security have a feature to check for registry errors and second, if not can I upgrade to a complete program for Norton that takes care of everything, including registry errors?