Dance of the Planets software is a dynamical simulation of the solar system. It is used in our laboratory to provide accurate simulations of the positions of the moons in their orbits around the planets. Dance is particularly good for simulations of conjunctions, alignments, and eclipses. It comes with a complete manual, and site licenses are available.
Link to Dance of the Planets at ARC Science Simulations
Here is a captured screen from Dance. You will probably need to adjust the brightness and contrast of your monitor to see all of the detail. If the text at the bottom of the screen appears mottled, either your viewer or your video system is not capable of 256-color display. Dance pushes the dynamic range capabilities of your video system.
This is a simulation of comet Shoemaker-Levy 9's encounter with Jupiter. This is a scripted simulation that came with version 2.7. Notice the status of the three pieces of the comet, displayed at the left edge of the screen. We find that Dance is particularly well suited to allowing the student to play "what-if" with a comet's orbital elements - seeing the effects on the resulting orbit.