I also doubt that errors are coming from Windows 7 - Much more likely to be something you've installed. If recent then consider using System Restore to go back in time.

Have upgraded 2 of my PCs to Win 8 on the special offer - Had problems applying updates to one but have sorted it I am now most impressed.

Post up your error messages and especially any error codes and let's see if the collective minds can get you back on track. Don't upgrade to 8 whilst 7 is in a mess as you will only copy your problems forward.