HELP! BUS DANCING

Hello, when I choose even one of the maps that I have ex; Grundorf, Spandau 1989 or another Map called Glendale, these 3 are the only ones that I have, and when I choose one of the maps ex Glendale Town and it's departure time, the bus starts dancing, and I can't control it, it also dances in Grundorf sometimes, and at the second I enter Berlin-Spandau 1989 and choose NEW and select the bus I wanna play with, the bus dances. I am running Windows 7 64-bit, and when I ran the game in Compatibility mode; Windows Vista the bus dances like it does now; it did dance more before. And when I choose Run in Compatibility mode for windows XP, it says test, and won't work?!.

Your system is too weak, load a presetting (e.g. "Minimum", don't know if it's called like that in the English version) and try it again.
If the bus is still jumping, you'll need to upgrade your system.

I removed the color from the title.

I will try to do that. Note that I have 4 Gigs of ram and 1.78 ghz Intel Celeron Dual Core CPU, and have Windows 7 Enterprise 64-bit Activated, but where do I change the presetting.

Go to the options, on the first tab page (somewhere in the middle) there is a dropdown list for doing that. This could also have been found in the manual

Your CPU is extremely weak for OMSI. I have 2.8 Ghz Dualcore and this is quite weak. Your CPU has to work a lot when you're running OMSI, e.g. physics and all the internal bus scripts.
Your RAM is ok, don't know about your graphics card, but your processor is the real problem in this case.