You are trying to be expert in 20 minutes, it ain't going to work ...
Go slowly at first, even forget real backups and stuff for the moment.
Test your system and setup first, just get freeware Nero CD-DVD Speed test program from http://www.cdspeed2000.com/ and try reading few DVDs. see how it goes. For clean pressed DVD-Video Single Layer. Dual Layer is different and slower. Close all programs you do not use, and do not work on the PC while the test is running.
Next test is get freeware DVD Decrypter and try to rip DVD-Video to hard drive. (no need to process further at this point, you are testing, not doing backup yet)
If any test is not "perfect" you need to fix your system before you suspect the drive or media. Maybe the IDE is not configured right, maybe cables, maybe something else.
Next test might be to use Nero CD-DVD Speed test program this time to burn a test disc, using Create Data Disc function.
So on ...
I also assume you are using official firmware that came with the drive, post its version, and do not change it until it is working.