We have had 2 computers exhibit the following fault in the last week:
1 - when right clicking on a hotlink, usually the 2nd option is 'Open in a new tab'. The first sign of the fault is when this option disappears.
2 - in one case I reloaded IE8, but it came up with an error (can't recall the error). On restarting the computer hung/froze at the point just prior to showing the desktop icons. Background picture/Wallpaper was there only. Nothing was active.
3 - In 2nd case I just rebooted the computer, and it did the same as computer 1.
4 - In each case there was an error message saying that Windows Explorer could not load due to a missing component (some file name ending in .dll).
5 - Off to computer Accident and Emergency. Fixed with all data intact. They have had at least 10 in the past week - all the same sympton. Explanation - 'there is a Windows update that had a bug'.
Maybe related, maybe not. Good luck.