I have drawn tiles in my XNA game and loaded my character. My character, however, doesn't move- the map does, which gives it the illusion of movement. Now I am wondering how to actually test against them for collision. I mean, where does the collision code go and how do I make all tiles represent 'one big thing'?
There's a tutorial on pixel based collision detection on XNA Creator's club. You'll need to figure out what objects you want to do collision detection on. I guess you want the character to move across the tiled background, so you don't want to check for collision between your character and the background. Instead you should make any obstacle s sprites and do collision detection on those.