Well, Runescape (optionally) is free, and you have to pay for the game/expansions with WOW. But, yes WOW has batter graphics, but it is also an installed game. For a browser game(in Java, aswell) Runescape's graphics are mind blowing. For a PC game, WOW's graphics are actually pretty horrible. I also see way more effort put into Runescape, than in WOW. But, I don't play either(anymore). I used to play Runescape(I was level 63), but only used friends' WOW.
World of Warcraft blows Runescape out of the water. You can't even compare the two. Anyone who says that Runescape is better has obviously not played WoW.
i once played WOW and when i first logged in, it was sooooooooooooooooooooooooooooooooooooooooooooooooooooooooo laggy! so i just stopped there and went back to runescape. so i like runescape more then world of warcraft.