The maintenance required light comes on at predetermined intervals to remind you that a scheduled service is coming due. On the 4 cylinder Accord, the maintenance interval for that year was for oil changes every 5000 miles. The maintenance light startes to blink about 500 miles before the service is due based on the elapsed mileage from the last time the light was reset. As you get closer to the 5000 miles being elapsed the light will stay on constantly.
so basically its telling you that you are nearing the time to get a scheduled service done on your car.
you can shut the light off if you've already had the service done. to do so, start by putting the igntiion key in the ignition but do not turn it on. then, with your left hand, hold in the button for the trip/reset for the odometer. (that button is at the bottom of your speedometer.)
while holding the button in, turn the ignition key to the ON position with your other hand. continue to hold the trip/reset button in until the maintenance light goes out. it will take between 10-15 seconds for it to go out. when the light goes out, continue to hold the trip/reset button in and turn the ignition key OFF. then you can release the button. the maintenance light will be reset for another 5000 miles.
you didn't say what the mileage is on the car. the service schedule can be found in your owner's manual. the shaking may be due to a normal maintenaance item such as a dirty air filter or it could be someihing unrelated. Mention it to the mechanic that you take the car to so that they can check the motor mounts and other possible causes.
hope that helps