Windows

Security
ESET AV / BitDefender / Kaspersky / Panda / Comodo / Emsisoft / Sophos / Trend / Vipre (very good with tough detections)
Malwarebytes (Premium works best)
Combofix
RKill
Roguekiller
Adwcleaner
HitmanPro (good for a "second opinion" scan, it uses multiple AV signature bases)
Lavasoft AdAware (the older engine was WAY better, but they changed it a few years back and it's nowhere near as effective now - but ThreatTrack Vipre AV uses that old detection engine still, and it really does do a good job)

Bitdefender live CD

Firewall
https://www.glasswire.com/
tinywall
comdo firewall