1997 SATURN S-SERIES SEDAN Engine And Engine Coolingengine Problems

OIL FOUND IN COOLANT IN MY 1997 SATURN SL IN SUMMER 2004 AFTER MINOR FRONT-END COLLISION. IN THE 2-3 MONTHS PRIOR TO COLLISION, I HAD TO ADD COOLANT EVERY 3-4 WEEKS, AS COOLANT LOW WARNING LIGHT WOULD COME ON. COOLANT HAD NORMAL APPEARANCE PRIOR TO ACCIDENT. CAR RAN FINE, TEMP GAUGE NEVER WENT ABOVE NORMAL. CAR HAD @ 78,000 MILES WHEN THIS BEGAN TO HAPPEN. ADVISED BY MECHANIC FRIEND THAT I HAD PROBABLY BEGUN TO DEVELOP A CRACKED HEAD BEFORE ACCIDENT, THIS WAS A COMMON OCCURRENCE IN SATURNS BUILT IN 90'S. THE COLLISION POSSIBLY WORSENED CONDITION. HE ADVISED THAT HEAD WOULD CERTAINLY NEED TO BE REPLACED, BUT CAR COULD POTENTIALLY RUN FOR SOME TIME BEFORE OVERHEATING PROBLEMS DEVELOPED-STATED I WOULD HAVE AN EXPENSIVE REPAIR, AND I COULD REPAIR NOW OR WAIT UNTIL I HAD TO REPLACE PART. HE ADVISED CAREFUL WATCHING OF GAUGE AND OIL IF I CHOSE TO WAIT....