oh... you can only burn data if you get the 25pc spindle of DVD-Rs
j/k what software are you using? If you are using Nero, just select file - new, and then look for the little tab on the top left of the window that pops up, and if it says CD, change it to DVD. Then you should see the option for DVD ISO, or something like that, then hit the "new" button on the right hand side of the window, and drag and drop files from the explorer window.
Good luck!
(oh, and if you aren't using Nero, you should be!

)
Punch Cards -> Paper Tape -> Tape Drive -> 8" Floppy Diskette -> 5 1/4" Floppy Diskette -> 3 1/2" "Flippy" Diskette -> CD-R -> DVD±R -> BD-R
The Progression of Computer Media