The Camera

Now I don’t know if this is exactly basic interface, but I notice that if I try to use the camera too far away from a set, the set dissapears, or is half consumed by the grey background.

I was wondering if there is a way I could increase the distance to which a camera could shoot a scene.

I have a lot of large sets so I have to decrease the size of my character, which slows render time incredibly, and doesn’t make them look very presentable ( rather more fake)

In blender 2.49 in the 3d view View / View Properties panel, increase the View Camera Clip End distance. Also select the camera and in the camera properties (F9) increase the Clip End value to use for your rendering.
In blender 2.5 they are in the Properties panel (N) in the View settings and camera object settings.
The size of your character should not increase the render time, rather than the increased number of objects you are trying to render that are now in the view. You’ll have the same issue by increasing the clip end value. The more vertices you want to render, the longer the time it’ll take…