Reapir maintenance 2008 Saturn aura

Car won't go over 35mph and 4000rpm and
all odometers are wonky won't read and
jumps back and forth started with the theft
system light and got worse and won't start
unless I rock the car back and forth until I
hear the neautral safety starter switch click
starts every time but don't want to drive it
with all other issues I also found out that the
battery in it only holds 350 crank amp so I
need a better battery hopefully that's the
problem any other suggestions greatly
appreciated thanks in advance