Have you checked on the motherboard's manufacturer or the chipset's manufacturer? The motherboard's manufacturer drivers usually are a lot of versions behind (yes that's you Asus).
The Verify is what actually confirms if it was a good burn or not: data on the disc is compared against the source image, and if there's a mismatch/read error it means the disc is bad.
Without the Verify you don't know if data on the whole disc is good or not.
Sounds like you need to install the drivers for your motherboard's chipset or storage controller. Use SIW to find out which model you have (look in Hardware -> Motherboard) and look in the manufacturer's website for the latest drivers. If you're not sure you can copy and paste the information from SIW and we can look it up for you.
Verify doesn't mess up anything: it just reads the disc again to make sure everything matches. And your problem isn't related to those 2 warnings, and since you don't have a log, we have no way of helping you.
I didn't say your burner isn't capable of burning dual-layer media. I said that it doesn't support the specific discs (or rather the dye/ink used to manufacture them) that you're using.
Your burner doesn't support the media you're using. You can try this firmware update for your burner (remove any disc and close the tray before updating then reboot after it's finished), but it would be better if you could get high quality media that your burner supports
IBQ queue files should be loaded with the Load Queue button of the Queue window (View -> Queue while in Write mode)
//edit I stand corrected, please read LUK's reply below
Update ImgBurn.
Try burning at 6x or 8x. Try a lens cleaning disc on that burner. If all that doesn't help please read this -> http://forum.imgburn.com/index.php?showtopic=8000
If the latest driver didn't solve the problem then I guess you'll need to either buy an IDE-to-SATA adapter to use your current burner or you'll need to buy a new SATA burner.
ImgBurn doesn't edit ISO images, and even though you could rebuild the original disc using ImgBurn's Build mode, it's easier to modify the files in the ISO image by using another program like UltraISO/MagicISO/PowerISO/etc.
Try burning at 4x. You might also want to try a lens cleaning disc on that burner.
If all that doesn't help then please read this -> http://forum.imgburn.com/index.php?showtopic=8000