iMac onboard CD/DVD issue

I loaded a DVD sometime back and it just locked in without mounting. Drutil eject cleared the disk from the drive. Later, compressed air was used and the disk would spin then silence then spin and silence a 1/2 dozen times or so. The drive would eventually time out and eject the disk on it's own. It was a small improvement. I next got a Memorex optidisc with 6 little brushes for an attempted lens cleaning but no change. My hunch is it's a lens/read issue. Does anybody know of anything else to try? The drive never had much use and has always been in a clean area.

iMacs, like MacBooks, use slot loading optical drives and they seem to have a very high failure rate alas. You have done the trouble shooting tricks. What does Apple System profiler (About this Mac) have to say?

PIONEER DVD-RW DVR-K05. I've always had good luck with Pioneer products but still never met a laser drive that might eventually fail some way or another. My mission is to instal w7 via bootcamp but understand that is not do-able due to some kind of OS driver issue installing from external USB drives.

If you print Bootcamp guidelines, sure it will tell you Windows must be installed from an internal optical drive. Like Pioneer personally, but slot loaders be slot loaders drat!