My 1996 Buick Skylark Limited won't start

I went to fill up with gas the other day and when I came out from paying the car would not start. We tested the spark plugs and they work fine, the fuel injectors all have power being sent to them, replaced the fuel pump and car still would not crank, all fuses are working, had to replace one that went to the computer. When use starting fluid the car will start up fine for about 5 minutes. Took the computer out today to try and get it tested but said they couldn't test it without it being on the car. The computer smelled like it had been burnt. I was wanting to know if you think the computer is my problem and if not what else could it be.