Can't Burn "Imation DVD+R" on Macbook Pro

Question

Hello, a couple of days ago I tried to burn some files on an "Imation DVD+R." I have an entire spindle of blank Imation DVD + R (Single Layered) and the computer refuses to burn any file on any of them. The discs themselves are in excellent condition.
When I used the "Finder Burner," I got the following error:
"The disc can't be burned, because the device failed to calibrate the laser power level for this media."
When i used an application called "Burn" and the "Disc Utility," I got the follow error:
"The disc can't be burned; it might be incompatible with this disc drive. Please try a different brand of disc, or try burning at a slower speed."
I went to the Apple Store and told a Genius what was going on. He put a "Staple DVD-R" and it worked flawlessly. He told me that he believed I purchased a bad "spindle of discs" because "normally Imation works just fine." I went home and tried to burn a file on the disc using my mother's computer (a PC). The disc burned flawlessly. I have about 30 blank DVDs that remain in this spindle. I would hate to get rid of all of them. What worries me is that I think my computer once burned these Imation DVD+Rs just fine (like I said, I really don't remember.)
I called AppleCare and was transferred to a Senior Manager. He said for me to send my computer in and he'll replace the optical drive.
Before I do so, does anyone have any suggestions? Is anyone else unable to burn these Imation DVD+Rs?
Here are some specs on my computer:
- Macbook Pro (Late 2008)
- Snow Leopard (10.6.4)
- Optical Drive is "MATSHITA DVD-R UJ-868"
Thanks for any advice you can give me.
Best,
--André

Answer 1

A brief update:
I dropped my computer off to FedEx on Thurs. evening (6:30 pm) and received it back on Sat. morning (8:30 am). That was incredibly fast!
Anyway, the following parts were replaced.
- ODD Super Drive (Symptom: Optical Drive Read/Write Data Error)
- Main Logic Board 2.4Ghz (Symptom: Sensors Test Failed)
- Optical Cable (Symptom: Drive Read/Write Data Error)
Moral of the story: if a Genius finds a "work-around" a the problem rather than trying to determine the actual cause of the problem, call AppleCare. Do not be afraid to speak with a Senior Manager (because, in my cause, the normal AppleCare technician didn't think anything was wrong.)
Thanks again for your all help.
Best,
--AL