The most stable version for turtlebot simulation is fuerte 1.8.11. I have been using this for quite some time and it is very stable. Tele-operation to autonomous navigation, everything works fine. But even with this version, if your computer is not good enough (less than 2.2 Ghz proccessor, nvidia graphics etc) the simulation with turtlebot might crash often or just two wheels of the turtlebot will appear etc.. (run top top on a terminal when running gazebo + nodelet manager + AMCL + rviz, you will understand).