I'm still considering Zone Alarm Free but hesitant because barely any of you recommend it.
Yep...problems. If you are using Avast Free, I would recommend OA Premium, which offers HIPS and other features for greater protection to layer your security. However Win7 FW is also very good. This is a comparison chart of OA free and Premium:
http://www.online-armor.com/. Do not get OA++ because it has the AV in it.
What every FW you decide on, trial it first to see if you like it and if it plays well with your other software.
You can also get Malwarebytes’ Anti-Malware (MBAM) for layered protection to use with Avast Free for an on-demand scanner; download
free http://www.malwarebytes.org/ (the blue button).