I'm having trouble burning DVDs using numerous methods HELP!

Hi,
My name is Corey, I am 16 years old and I know alot about computers. I am having trouble burning DVD's. I would like to learn how to make backup copies of some DVD's that I own, and I am having lots of problems. The problem that I am having the most is when I can actually get the DVD to burn, when you watch it the DVD will skip, freeze, and will get huge pixelated areas on the screen at certain momemts of the DVD. I have tried many methods before but none of them seem to work flawlessly. I do have a few DVD burners in my house and I have tried all of them. I have tried using DVD Shrink, Alcohol 120%, and I have tried copying a DVD using Easy CD/DVD Creator. I don't know why it isn't working, I don't know if it's my hardware, if one of my settings is wrong, or if I am just doing everything wrong, but I tend to think it's not my hardware since i tried it on different computers. I would like to hear from you guys what methods you guys use to burn DVD's and how to do them. I would also like to know if your methods get by copyrights. HELP ME PLEASE!