Computer protection

[Shourty]

I have been using norton on my computer for over fifteen years. I have some program booting and other lag issues that I attribute to that program.
Often I want to cancel them and get something less invasive.
Without all the rants and flames that this forum is known for, what do you champions of Norath suggest?
Not that I'm free from throwing flames or going on rants on occasion, just, not this time please.