iyogi tech support a real problem.

I purchased an Epson work horse 545 printer. I made a mistake in setting it up but had a service agreement so went on line looking for Epson tech support. I thought I had found it, it wasn’t untill I had logged off that I realized I had iyogi web site. They had asked to take over the computer to fix the printer problem and I let them. After an hour the problem wasn’t fixed. They ran a scan and found nearly 800 infections, I knew this was untrue and they wanted $200 to fix it. That’s when I realized I didn’t have the Epson web site. I said no, hung up the phone and logged off. Now the background color of my screen is off and I am having a hard time telling the difference between red and black. Called them back and told them what had happened and asked to have the colors corrected. They said they would but I would have to pay to have it done???? So at the moment I have off color screens plus I am not sure if they still have access to my computer or not. Would appreciate your comments