2005 Dodge Neon Car hesitates

2005 Dodge Neon Automatic 78000 miles

So I started realizing that when I first start my car in the morning and have to stop at a red light right in from of my house ( maybe 3 minutes after starting it ) the car will "hesitate" when I release the break and push on the gas pedal. It feels as if the gas and break are pushed at the same time and it buckles a bit ( sorry best way I can describe it). So my friend told me to let the car run for a while before I start driving and it stopped doing it for a while. This morning I had the car run for about 3 minutes, pulled out, drove down my road and it started stalling. I had to restart it to get it to move. I pulled over to the side let it warm up some more and then it worked fine on the way to work. A couple of weeks ago my check engine light came on. Well I work at Sears, so I had the Automotive department hook it up to the computer and they said it was just a sensor and overwrote it. ( They never told me what it was :-(( ) Well tonight my check engine light came on again. What could be wrong with it? I am a little scared to drive now, since it's my first car and I have not a clue about cars whatsoever. BTW once the car has been running for a while it is just fine, I had several friends driving it and they all said it drives smoothly.