for the shakes, chances are you have a bad motor mount, chacnes are its the top mount. bad mounts are most noticible at low RPM at moments of high torque(starting from a stop) here is the how-to -
http://www.saturnfans.com/forums/showthread.php?t=24000
if the overheating, chances are your ECT has cracked, a common failure point of saturns. here is the how-to -
http://www.saturnfans.com/forums/showthread.php?t=24003