2000 Nissan Maxima Engine light

Hi,
The other day all of a sudden I started seeing the Engine Light on my car panel. One of my friend suggested me remove the Negative terminal of the battery for 20 mins and put it back and check if it comes back again when the engine is started. The light didn't come this time, but the car was behaving very strange. The engine used to idle for a couple of minutes and used to shut down. I restarted it and this happened a few times. After this the engine started idiling but there seemed to be lack of power in the engines. No matter I pushed the pedals, the vehicle wasn't moving forward or if it moved it moved very slowly. I clearly felt the engine wasn't able to power the wheels. After a few trails runs, it started moving but the acceleration of the is very slow. I'm not sure what could be the problem here as I'm not very good with Cars.