No need to apologize for a lack of knowledge. That's what the forum is for. Far better to ask and find out than to blunder on until the computer goes disks up 
.
It's been quite a long time since I used SpywareTerminator, about 2 years, but there should be a block list available somewhere, that should give (hopefully) adequate information as to what it is that is blocked, and if we're real lucky, the file name and path. This is to do with the HIPS module, a behaviour blocker.
Had you updated any software, by any chance, (maybe from Avast 4 to Avast 5) at around the same time as this ST warning came up?
I'm thinking that maybe it is a valid process that was blocked by ST, and maybe that could have prevented Avast from starting?
There is also the chance that it is malware. A Winsock change would be more likely to be malware than a FP, I'd think. Please also check ST's quarantine for anything that was quarantined around that time. The use of System restore may have masked what is actually going on, but this may not matter if everything is working well now.
Indeed
ST's block list gives the file name and path, but it's simply in the system32 folder as svchost.exe, which I understand is an important host process for Windows, and isn't helpful as to what was trying to run through it. There is nothing in the quarantine list either.
I don't recall any updating any software. It's also possible that the svchost process had nothing to do with it at all, it just seems likely because when the HIPS warning box first popped up, I had to keep clicking the option (at first allow, then block as I got suspicious) for awhile before it went away.
To recap:
I have a small episode with ST and the svchost, which I promptly forget about.
Roughly 4 days later, I turn on the laptop to find it running very slowly.
I restart it, to find Windows Security Alerts telling me about Avast and Windows Defender, Update, and Firewall being shut down. I can't start any of them and realize I have an infection. As I recall, Spyware Terminator was turned off as well. I had no warning at all. I promptly turned off the network switch and shut down my laptop.
A day or so later, I start seeking help here. After not being able to start Avast in safe mode, I use system restore and restore to March 4th (I would have gone farther back, but didn't have many other restore points). After the reboot, everything is running again. ST tells me about the svchost process trying to run again. I remember about the earlier episode, and add it to the block list. I scan with MBAM with no results. I update Avast from 4.8 to 5 and reactivate, run a scan with that, and get no results there either.
My laptop seems to be running fine now, but the reason I'm still worried is that the infection was quite serious, yet nothing was found in the scans and I don't trust System Restore to eliminate the problem.
Also, if there's anyone else who had an unknown infection shut down avast and windows security, please feel free to post
