Level geometry runs even slower than models, especially for the size of the objects I have. For example, the restaurant world's floor is like 32,768 by 24,576 quants total. I once made a wall in my old project and it took nearly an hour to build and compile, 99.9% of the time spent just tessellating textures. Yet, level geometry appears much darker than regular models without shaded mode and the surfaces are likely to be very large and could cause trouble.
I could combine some models, but that would mean gigantic skin sizes (like 2048x1024 (using 4 MB of memory)). Though, from my experimenting, skin size has practically no impact on the frame rate. The table areas, for example, in my restaurant world consist of two chairs, a table top, a table bottom, a salt shaker, a pepper shaker, and a napkin dispenser (7 models). These four entities can be combined into one without too much trouble. They're relatively simple in their shape with quite few polygons (mostly because of those straight edges). Another part of my restaurant world consists of booths instead of chairs and basically the same basic stuff from other areas. This, too, can be done as one single model, but again with a very large skin size. They don't animate and there's no need to animate them, add shadows, etc.. However, using a regular bounding box may pose problems, so I'd have to turn polygon collision on for each object. The bounding box is okay for the platform levels themselves as, well, they're already rectangles. It's the scenery of each world that has the odd shapes.
I'm looking into getting a 2 GHz processor, though I don't know what my motherboard supports. My motherboard is K7VTA3 version 6.0. I have a Duron 1.05 GHz processor right now. Anything much above 2 GHz is too expensive at this point. I've seen 2.5 GHz for $100 is is more than my budget can handle, let alone trying to get a more dependable graphics program that isn't so outdated as well as getting XP if that would help, but before I can get XP, one specific problem needs to be solved (and it's not monetary related).