There are a variety of Flash-related viruses going around - I have one currently that comes with an "update now!" pop-up, although there are enough misspellings in the text that I know it's not legit. I'd run a thorough virus scan as well.
Difficult to capture the whole desktop activity. Interesting to note- I'l close the error window, and can use CH for a while, but then another (and sometimes another and another) error comes up. Frequently stopping Safari altogether and making me force-quit.