Minutely better. DVI is digital, the other is analog. The vid card is producing a digital signal, which it then converts to analog to send down the wire, but your LCD is a digital device so it reconverts it back to digital. It could save a little time and look a little better to just use DVI, which skips the conversion to and from analog.
If you've got an analog monitor (CRT) then it's a moot point.
Also, we're talking fractions of a second, I bet. You might not notice any speed, but then, maybe (just maybe) you can tell the quality is better. Try it and decide for yourself.