No, no, NO don't just delete wintest.exe!!!! We have no idea what it actually is! A wrong fix can really complicate matters. HiJackThis is truly not a "fixer" program, it is a scanner program. Yes, some fixes can be made with HiJackThis but many, many cannot! It is first of all a program to show us IF there is something there...once we see there is then we must find out exactly what it is we are dealing with...the OTHER things you have been advised to do should hopefully give us a clue as to what exactly is on the computer and HOW to remove it. Just deleting a problem will not make it go away.
This could very well be a serious infection, requiring special tools to remove.