Windows 7: Boot, Startup Repair issues & call from Pakistan Boiler Room

ZT desktop used only for Microsoft, Cisco, CompTIA training and flight sim. All up to date, no changes or problems until two days ago; integrated HDMI quits, use XFX 5750 HDMI, re-boot and goes right into Start-up Repair or Start Normally but always goes into Start-up Repair. Hours letting it get to and go through "attempting repairs, repairing disk errors, could take over an hour".
Two days after it started, yesterday, a call from "UNKNOWN CALLER". Won't go into all the details but it was obviously overseas, a boiler room with multiple scams going, and was going to hang up immediately when he proceeded to tell me my version of 7, the problem I was having, the dropped my name and obviously had my phone number... long story longer; he said for a "one time registration fee, he'd fix my machine". I told him I wasn't paying him anything, hung up....
Still trying to salvage my box, really don't want to do a clean install. Wondering if anyone else has had this problem, been contacted by South Asian-type people trying to scam others after poisoning machines? And if so, any luck repairing this short of clean install?
Religious about updates, patches, security and have four machines total, this is only Windows 7, never any problems with other 3. Welcome ANY thoughts. Thanks.

Starting with disinfection, work through steps here: Windows 7 fails to boot

Is it possible your manufacturer might have sold registration/warranty info to 3rd party service providers whose call was a coincidence? I have read that it is best not to register for this reason, since your warranty is good whether or not you register and often will start it's countdown only after your first Support call.

Thanks for the reply. Not sure, but could be a possibility Mfr did sell my info, but not convinced cuz I upgraded from H.P. to Professional (and they knew it) through Amazon and didn't register it so unless Amazon gave out my info, this was more sinister than that. I could barely understand a word ANY of them said, and I was handed off five times "to my supaviza" who tried to take it further. And the one common line from each was "you have corrupted files but we can fix it for you." But when I pressed for specifics about which files where, that's when it became even harder to understand what they were saying.

I'll keep working at it, try anything at this point. Appreciate the help.

Next time when a call like that comes, just hang the phone.

Have a good anti-virus product and a good firewall.

Have and have had both good antivirus and firewall. Kept it very tight. Did a clean install, antivirus first w/updates, firewall, windows update overnight. Rebooted the next a.m. and went right to Start-up Repair and same grief.

Completely baffled and not sure I want to proceed with another install unless I know it's not going to be a waste of time.

Thanks

A call FROM a support technician ( or whatever they are ) IS HIGHLY UNUSUAL in my opinion. What exactly are you using to repair, reinstall with ? A recovery partition ? I think using an ISO with your key will solve your problems.

Reset the BIOS to defaults, wipe the HD, follow these Clean Reinstall steps to get a perfect baseline install.

SSD - HDD Optimize for Windows Reinstallation

That's what I thought, but nothing is working like I thought it should. Using OEM software and this last time around, I got as far as upgrading to Professional, spent an hour plus downloading and installing 75 updates (all while a/v and firewall up and running) but then got "not responding" and no way out of it.

Started all over again, now it won't let me install to partition, won't let me do anything as far as deleting, creating a new partition, formatting...nothing...

Frustrating because I'm always on top of updates, what goolies are out there and don't use the box that much. I've got two other machines that haven't been touched, had any issues whatsoever. Murphy's Law and I'm fed up with it....

Yes it`s very frustrating, especially when you don`t use it that often.

What OEM software are you using? Recovery DIsks? Have you tried clean reinstalling with the latest Windows 7 with SP1 ISO download?

Win7 Home Premium x64 SP1 English Official ISO download
Windows 7 USB-DVD Download Tool
Clean Reinstall steps