the only purpose for internet explorer, is to download & install google chrome.
firefox used to be my go-to, but they sold out to yahoo and now anything you do via firefox redirects through yahoo search engines...even if you designate google has your homepage and default search engine, it will ALWAYS reset itself to yahoo's garbage redirects.
I still use FF. I've never had it reset to Yahoo. Now granted, I am running the Linux version, but that shouldn't be a factor, but one difference that I thought I should still mention.
One that is lightweight that you might want to look at is Midori. For Windows it also has a portable version, so you don't have to install it, just click the exe file and it runs. I like versions of programs like that. I have a digitizing software package that's portable written in the Win 98 days, but because it's portable it will run flawlessly on Win 10.
Considering our ISPs are essentially Google now, as far as privacy goes, not much can do. Especially with the browsers listed here. Even with their privacy features, it will only get you so far.