There are two separate lasers in DVD burners, one for DVD and the other for CD media. If you have problems with CD only (both pressed and burned discs) the it is probable that the drive is damaged. You can still use it to read/write DVDs, but it is useless for CDs.
To be sure that the drive is damaged, try this simple test. Try to boot from a CD disc (a good test is a live distribution of Linux). If the computer is able to boot from the CD with no problems, then the drive is certainly working, and the problem must be somewhere in the softwares installed in your computer.
Be sure to set correctly the boot sequence in the BIOS, so the first device boot is the LG drive, or this test will be useless