The most common things I find are addons like CD/DVD emulators, torrents and infections. The other times its a failed drive.
Whenever I insert disc (brand new & tried with many new scratchproof disc) system starts hangs.
It continues to remain freeze even after disc is ejected from drive and computer does not become OK.
To overcome, need to press restart or to hold power button for few seconds to completely stop and then start again.
I have tried inserting disc in "safe mode" also but problem persist.
I did not try my DVD drive in another computer to find whether it is ok but what could be the problem.
either DVD drive or data cable of drive or software issue.
Window 7 ultimate
gigabyte GA J1800M D2PN
4gb ddr3 ram
WD 160GB HDD
SONY DVD writer
450w power supply