It is always a good practice to run scans if something seems to have changed your pc without you doing it. In my case I have young kids playing on the pc's and sometimes they do things that are hard to change back if you don't know what they did. This does not seem to be your problem. As you say you turned of the pc and then restarted in the morning. Sometimes I do system restores but that should be last resort. Did you look at windows update to see if a update may have caused this problem?i have tried the screen resolution and apparently it is on the recommended,even in here the tabs and icons are large. could it be malware then as Rich says?
