So far, the new OS is behaving nicely. Haven't had to reboot, haven't
seen the BSOD. Got pop up warnings that a couple of my older software
programs were not going to work, so I stopped their install. New system
hasn't belched yet, either.

I'm using AVG anti-vi at the moment, a freebie trial. It is not
intrustive and seems to have little impact on speed or resources. I gave
up on the Norton stuff about a year ago.