I disagree very strongly.
1) What appears to be smoke may not be smoke at all. If it is smoke, you have no idea at all what is happening. It could be vapour from wet, hot brakes. It could be fuel vapour from an engine that has been shut down too rapidly. It could be anything. You have no idea at all if you're in danger or not.
2) While the seatbelt sign is on, and until an evacuation has been ordered, you should be sitting down with your seat belt fastened. As soon as passengers decide to do their own thing, chaos ensues. That is when people start dying. You want to be the cause of that?
3) You don't have a quarter of the information the guys up front have available to them, from other crew, from ATC, from ground vehicles/handlers etc. You have no right whatsoever to decide you are going to initiate your own little evacuation. If an evacuation is about to be ordered, you will be distracting the cabin staff quite significantly from their duties in getting people off in as orderly a manner as they can.
4) Even assuming that you can sidestep the cabin crew, open an exit, blowing the slide, possibly with the aircraft in motion at time, you don't know what vehicles are around you. Are you about to get mown down by a firetruck? Or are you about to cause one to swerve into the path of another, thus taking out two truck that were about to assist at the scene of a fire at which all assistance is needed?
5) If you're really that nervous, you can always ask for an exit row on checking in. If your behaviour is what it's likely to be based on that last post, an exit row is the last place I would want you sitting.