Will not start

We have been looking at the usual suspects (battery, starter, etc.) But there have been some other strange things happening that might be factors. First, it has always started right up with no hesitation. But for the past year, it has been intermittently stalling while driving, but immediately restarting. This was accompanied by the check engine light coming on, and a sensation of surging. Since it is a '95 and wants the goofy OBD 1.5 or the Tech2 code reader, I have been unable to check the codes. Usually, the check engine light went off after it was parked. Then about a month ago, it seemed to have a dead battery, but it started with a jump box no problem and I figured weak battery but alternator okay. However, my cigarette lighter port stopped working for no reason. Then, if it sat for a day without being started, it was dead again. After several tries with the jump box, it started, but there was some smoke on the driver's side near the firewall. That went away, so I thought maybe something had spilled in the engine compartment. That was the last time it started, and we have tried jump starts off the jump box and off other cars for 3 weeks now. My battery is a cheap one but is only a little over a year old. It only gets to about 12.4V at most after trying to jump it. If it has been sitting, the battery is drained and I get nothing when turning the key, but if getting an assist/jump I get the rapid clicking until the battery goes back down. I have manually checked and thumped the starter but have not checked voltage to the starter. There was some minor corrosion at the neg battery terminal, which I cleaned off, but no change. This is my only vehicle, and I am in a tiny rural area with no other transportation, so any help or ideas?