spiderman: good action...plot...bad dialogue
X-Men: too lil action...plot was kinda cool, but felt too much like "just an episode" rather than a movie-worthy plot...dialogue was ok
X2: better action, better plot, better dialogue...but the experience didn't feel totally breath-taking or anything...(sorta like been there, done that)
spiderman gets my vote since it was more original and had a plot that didn't feel like just another episode...
but i doubt spiderman2 will be very good...the main appeal of the first spiderman was the discovery/experimentation with new powers...won't be the case with the second...
as for why X2 didn't get my vote...i guess i'm just a bigger spidey fan