Burned DVD-Rs and DVD-RW's won't mount

Question

Hardware Overview:
Model Name: iMac
Model Identifier: iMac4,1
Processor Name: Intel Core Duo
Processor Speed: 2 GHz
Number Of Processors: 1
Total Number Of Cores: 2
L2 Cache: 2 MB
Memory: 1.5 GB
Bus Speed: 667 MHz
Boot ROM Version: IM41.0055.B08
SMC Version (system): 1.1f5
Serial Number (system): W8619*U2P
Hardware UUID: 00000000-0000-1000-8000-0016CB897C7A
MATSHITA DVD-R UJ-846:
Firmware Revision: FB2U
Interconnect: ATAPI
Burn Support: Yes (Apple Shipping Drive)
Cache: 2048 KB
Reads DVD: Yes
CD-Write: -R, -RW
DVD-Write: -R, -RW, +R, +R DL, +RW
Write Strategies: CD-TAO, CD-SAO, DVD-DAO
OS X 10.6.6 Snow leopard.
Hi there, I have been experiencing this problem on and off with various media types (originally I had issues burning to any disc - cd or dvd- I upgraded to Snow leopard, and the problem was fixed).
Now i'm having issues READING home-burned DVD-R's, DVD-RW's ( I avoid using DVD+R's). Commercial dvd's load fine. I can burn to blank DVD fine. I have cleaned the internal DVD drive with a VCD cleaner, and tried resetting the SMC (http://support.apple.com/kb/HT3964).
I use an LG dvd recorder at home. The discs I use are SONY DVD-R and DVD-RW. These play without error on the LG dvd player.
However when I try to load the burned discs into the mac, the drive makes a whirring sound and spits out the discs within 10 secs. These are new discs with no scratches etc. I have tried setting the CD&DVD system prefs differently (opening the dvd in disk utility, finder etc) to no avail. I tried both finalizing the discs and un-finalizing them on the DVD player.
This is driving me nuts as I am a film student and need to access my burned dvds!
note: I recently had my computer serviced in the last 6months as the hard-drive failed (I live in Christchurch, NZ and the computer was damaged in the Sept 2010 quake). The comp was relatively undamaged in the more recent Feb 22nd 2011 quake, but because of the shaking, could there have been substantial damage to the internal disc drive in this case??
any help would be greatly appreciated! Cheers
<Serial Number Edited by Host>

Answer 1

• Avoid the top five disc-burning mistakes:
http://www.computerworld.com/s/article/print/9005547/Avoidthe_top_five_disc_burningmistakes
Not sure what else may be the cause of the issue; but if there's
a chance of other hardware damage after an earthquake, it
may be wise to have someone check over the computer.
{I've asked this post be moved to the Intel-based iMac forum, yet the issue
is likely a generic one not limited to a build model vintage of computer. My
name's avatar is of the representative PowerPC iMac G4, of this forum area.}
For general disc burning, I use a small free-ware utility that makes it clear
what I may be getting; of course it makes quick work and the other methods
function correctly on my Macs... see http://burn-osx.sourceforge.net/ and use
it with the setting for it to make discs that will work in Mac + PC. Worth a look.
Good luck & happy computing!