Well yes and no. Both have a 2.2 four cylinder if I'm not mistaken, but I don't think the earlier Cavalier's have the EcoTec motor. And you should be able to get the engine from the '03 into the '97...
can't really answer that completely. I'm doing my son's 95 Pontiac Sunfire and using a 97 donor car. First: make the body repairs to factory specs. the car needs to be fairly staight for new sensors...