best to least:
DVI
VGA
Composite (green, blue, red)
S-video
Component (yellow) /w red, white sound cords
never ever convert downward, you can always do it, but it blows.
converting upward actually gives better refresh rates, however no change in quality
dvi,vga, and svideo come with and without gold shielded wires also, and it does make a difference on a computer monitor, but you wont notice on any tv