Originally Posted by lalec
Make sure you are using a good usb cable.
^^^^ That. (and try a different USB port on the computer - on a desktop, try to use the ports on the back of the motherboard)
Also, check to see if you have the Samsung USB drivers installed.
I don't think USB debugging is required to connect phone to PC (I've used Odin, and have transferred files using regular explorer and never had USB debugging enabled)