Just a note to spread accurate information:
Seasons are caused by the axial tilt of the Earth, and the change of that tilt with respect to the sun. A planet with 0 percent tilt would have no seasons in a circular orbit.
2nd: An eliptical orbit can be very stable. In fact, Kepler asserted that even the earth's orbit is elliptical as are all orbits around the sun. Comets for example have very large orbits and are elliptical.
3rd: If the earth was on a large elliptical orbit, seasons would take place, but they would be global seasons, not like we have them now where they depend on the hemisphere.
Just a little helpful information from an Astronomer.