First let me give you a little advice. Try to make it clear, simple, complete, but not so long to read.
Now, you have several "layers" of different and unrelated issues.
The first one, to verify if there is really some malware or not.
For that, I would recommend posting here in the subforum "Viruses and Worms". Again, "KIS(S)" (keep it simple). You should provide there the suspicion of which malware, your Avast edition and version, and the exact OS (which Windows, SP, 32/64 bits). They will request from you to download and run some programs so to report back the resulting logs.
Then, you can come back to the "removing old security tools". For each old security tool you ever had, you need to run the respective removal utility. A partial list is located at
http://singularlabs.com/uninstallers/security-software/.
About the Avast offer, you may contact sales A/t avast d 0 T c0 m .
About the iYogi situation, there are not much we (simple Avast users like anyone else) can really do. I'll try to get the "right" Avast Team member to look into this (but no promises of getting anything concrete).