How should I create my world for my side scroller?
Should I use tiles or are they pretty much obsolete?

Should I just use a bmp image that is much bigger than my screen resolution (ex: screen: 640x480
world: 640x4569)

Or is their another, better method?

Thanks

I think you'd better go with the tiles. There still good to use. Better than creating that huge bitmap. That will easily be a couple of megs, and you'll have to store that in memory. Go with the tiles.