Having done some further research on my kernel panicing iMac I am wondering if it is getting too hot?
I had the hard disk replaced recently under Applecare and there are a few posts on the Apple Discussions Forums that show a few people are having a similar problem to me. Alas there is no simple or easy solution, which is frustrating.
I am now trying to work out what is causing the iMac to work too hard so it gets too hot and it appears that Flash may be part of the problem.
I am not sure what to do next, I think I might see if I can improve the airflow around the iMac, and also if there is a way to force the on board fans to start running at a lower temperature, ie before it gets too hot and then crashes.
Longer term I might replace the hard drive, 1TB is too small anyhow, so I would put in a bigger disk, tempted to put in a small SSD and then replace the DVD-R drive with a traditional hard drive. Might lengthen the life of the iMac for another couple of years. It is an i7 with 8GB of RAM so it is still very powerful.