I/O errors are reported directly by the drive and they can have a lot of different meanings (i.e. not all I/O errors are the same). That's why we ask for the log, so that we can see the I/O error description.
First of all, update ImgBurn to the latest version.
Your burner doesn't support the discs you're using, so please read this: http://forum.imgburn.com/index.php?showtopic=8000
It's your burner that's returning those error codes. If you use an older version of ImgBurn you'll have the same errors.
The burning process relies on the burner/firmware/media combination: if the burner is good, the firmware is the latest then you should try with Verbatim 2.4x (MKM-001-00 dye) Made in Singapore blanks to rule out media as the problem.
It takes 45mins to burn at 2.4x, which is the lowest speed possible on +R media, so if yours is taking more than that, then you have a bigger problem. Of course if you posted the whole log from that burn we could've seen this earlier.
Use Media Player Classic Homecinema to open the VIDEO_TS.IFO file created by ConvertXtoDVD, does it play OK? You can also try with PowerDVD/WinDVD to open the VIDEO_TS folder.