I had an issue with a little rectangular box that would pop up when I opened Parallels. I went to their forums on their website to no avail, then went to chat with them.
The tech after logging onto my new MBA was able to rid the computer of the annoying box, then asked if there was anything else I needed assistance with.
I mentioned that I read that my paid version of Parallels 7 allows it's own ads and if there was anything that could be done. He/She put me on hold and came back to do something in Terminal, putting in a command of three words that did not make sense, then had me log-in. She said done!
I was getting an ad at least once a day. It has stopped so far, but seems to me that it's more than just checking or unchecking a box to rid the software of that annoying feature.
Hope this is helpful to you!
Thanks