but you would think there would be some odd shapes of planets after the disintegration of stars. Also the orbit spins, are these constant through time, or is there a slow down or speed up?????
A planet can be an "odd" shape up until it reaches a certain size, then it being to collapse on itself form it's own gravity and is forced into a sphere/spherical shape.
Orbit and spin are caused by gravity, also. To be more specific, the sun's gravity. So, in theory, the gravity keeping them spinning is actually static and should the sun's gravity ever change, then the orbits, which could possibly lead to the rotation of the planet changing (speeding up/slowing down/nothing at all).
The closer to the sun, the faster it moves. The same goes for it's inverse. If there was a way to change how close/far the planet was from the Earth, then it would slow down/speed up to correct the change in distance from the sun's equator.