Windows Defender + MalwareBytes Pro—been my combo for quite a few years. Very good, doesn't chew system resources.
If someone said I had to change, first one I'd look at is Nod32 from Eset—that was excellent when I used it ~10 years ago. Also good experience with Kaspersky.
I would avoid McAfee & Norton based on old experiences—but of course they could be great now.