1994 Saturn Car will not start

Other Category problem
1994 Saturn 4 cyl Wheel Drive Type unknown Manual 200000 miles

My car was having a problem engaging when I would go to start the car. It made an awful screech noise but after about 1-2 tries it would engage and start. Now it does not engage, makes an awful noise then a loud boom at the end. I have tried several times over a two day period and it still has not started. My batterey is old cables somewhat corroded could this be the problem? With the loud boom? Or is it the starter or soleloid or alternator. Any suggestions would be helpful. I do not have any money for repairs and need to get to work this weekend for xmas money!