I think I liked your 'Boring stuff' config! Firefox has not worked as smoothly on my own 8.1, & I'm wondering if I should join you with Nightly.. Each firewall mentioned was on a list of possibilities for my XP system. I wanted Online Armor, yet chose "Private Firewall"free. I do feel the Firewall with UAC built into your Windows 8.1 already manages the system quite well, although I agree with Gnosis, & swear by Sandboxie! http://www.sandboxie.com/index.php?DownloadSandboxie It won't let anything onto your system, & isolates all unwanted flotsam & jetsam before it can reach your hard drive like aluminum foil in a pan. When it's time to end your session all is deleted along with the contents of the Sandbox. You'll see. HitMan Pro literally revived my old XP computer, & extracted items I'd thought I'd swept long ago, but with your 8.1 you've no need to worry ..unless you'd like to trade down for my XP, j/k! Free may not always equal Great, but when speaking of HitMan Pro & Sandboxie it just might!Boring stuff, pretty much.