I was simply trying to allay your fears about this in that it is not harming your system. If you are constantly having to delete the file, that means it is coming back in the reboot. The reason why it is generated when visiting a certain website is most likely due to that website using plugin131_18, this would create a log file or "trace" of the visit.
The info that you found is pertaining to those particular processes which you cited and if you read further into each process you'll see that they pertain to log and dump files.
This explains what a .trace file is
http://filext.com/detaillist.php?extdetail=TRACE
and this is what plugin131.trace is:
http://www.google.com/search?q=plugi...=&start=0&sa=N
I just don't want peeople to panic and start deleting files from their PCs unnecessarily.