Windows Phone Scam + Computer Crash

Hey I just experienced a system crash after receiving a call from the windows phone scam guys.  A few days ago my new desktop computer had a bsod DRIVER_IRQL_NOT_LESS_OR_EQUAL and thought that was a little weird since it has been a solid computer.  Now a few hours ago it sounds like I got a cell phone call from the windows phone scam guys and probably I listened a little longer than I should have and he kept on going on about windows servers and said my computer might crash if I did not get it fixed.  Well I hung up at this point because I realized it probably was a scam but my computer did crash about an hour after the call with the same error I said before.  Now I am wondering what steps should I take to make sure my computer never crashes again.  I guess this could be a coincidence but it was still kind of alarming.  I am all ready scanning for viruses and was wondering what more steps I can take to safeguard my system.

-Thanks for your time.