Norton is a bit of a tricky one as some PCs get on with it and others just don't. You'll find a lot of people saying "don't use Norton it's slow and terrible" etc. and a lot of others say it's fine. This is because of the different combinations of hardware and software that Norton has to run with. If you've run it on your PC and it's fine, it's best to try a trial version on the laptop to see if it runs ok. AVG is a free program so doesn't have all the bells and whistles that Norton does, but it's fairly light and won't slow down the computer too much. I use it and it seems to do the job just fine.