MSE, agreed, is very easy, compatible (obviously,) and reliable.
Malwarebyte's Anti-Malware is CRUCIAL in my opion; it's a standard, which is a fact.
I recommend (A/V Avira AntiVir Premium Security Suite [note: Very sensitive at detections, if you use "unofficial software," this is not for you] or Avira AntiVir Personal Free); TrendMicro Titanium Maxiumum Internet Security is PHENOMENAL, but conflicts with Malwarebyte's (PER TREND SECURE, the manufacturer... I re-installed after installing Trend Micro recently and it seems fine. It has to do with the fact that Malwarebyte's STAYS "on-demand," as-in free version STYLE, not active or a live background process.)
An underestimated and overlooked program I rely on is SUPERAntiSpyware Pro. If you want a free version, skip installing "SUPERAntiSpyware Free," and simply use a USB Flash Drive (with ReadyBoost benefits, why not?,) and go to SUPERAntiSpyware.com; click "Download PORTABLE Version," then click the red icon / banner. Save it to Flash. Notice it always saves the most current revision as a different file name. It's smart, as it avoids spyware that's been programmed to recognize typical A/V-A/S-A/M processes-services-etc. Just as good as Free Edition, just as powerful, but 1 less thing to install.
Spybot Search & Destroy; easy-to-use; has "immunization" (for browsers) + cool features: Lets you load-up a hosts file database (comprehensive list safer-networking.org compiled of malicious sites that they inject into your hosts file to permanently keep your computer blocked from them.) It also allows for "TeaTimer," which gives you "Allow? Deny?" popups when system changes occur. BOTTOM LINE on this: GOOD if you can't figure out an infection or how to get rid of it. Malwarebyte's is the first step, then A/V program of choice, SAS Portable scan for good measure.
If you are a Comcast ISP subscriber, they provide Norton, but I've used in length and have seen it miss detections.
I hope this 2nd opinion helps.