We are now up to V 1.41, and the Database is up to 3270
You need to uninstall your old version then download the current version and then update it (it is found in the 8 Step Guide)
Norton Internet Security has many startups and generally can slow systems down (debatable)
When does your subsciption expire? If it is soon, I'd uninstall it then run the > Norton Removal Tool, then Restart
If you do decide on removing Norton, you will need another Antivirus software
I would suggest > Free Avira Antivirus (of which I use)
Update it and run a full scan