Nawlej, there are probably plenty of ways around this but in my experience, I did this a few months ago using Smartripper. Because DVD Singles have other information on them it is important to select the correct Program Chain if you just want the music video only. Here's what I did:
On the main INPUT screen of Smartripper, in the first box:
TITLE -> PROGRAM CHAIN -> ANGLE, click through each Title until you find one of the shortest (in minutes and seconds) ANGLES. Click on this and the program
should select the correct chapters in the VOB's for you. Once you've ripped these, load them into DVD2AVI and scroll through the picture to check that you selected the correct CHAIN in Smartripper. If not, try again but to get the best quality MPEG file, I highly recommend using Chickenman's tutorial, found here:
http://forum.cdrsoft.cc/showthread.php?s=&threadid=160, stopping after the TMPGENC stage. You
may have to experiment with the SETTINGS button or STREAM PROCESSING tab on Smartripper to get the correct files, but don't give up trying...it IS possible! Good luck.