Car Troubles, Steering wheel and dash shake when stopped?

I just bought a 1995 ford contour recently and it had a couple problems. I replaced a Mass airflow sensor and plugs and now it runs great except however when I'm at like a stoplight or have to stop at all. When i stop, the car interior shakes like the steering wheel and dash it's pretty annoying. What's the problem?

It's not running on all cylinders at idle. Not a good car to start pouring repair money into.

Waddling or shimmying as you press the brake is caused by warped brake rotors on the front wheels.

I find some peoples answers to be amusing to say the least. Like the one about not buying 15 year old cars.
I guess since your car is 14 years old you just squeezed in.
I own a 1993 Ford F-250 work truck that still gives me great service. I have a 1993 Volvo 850 that still runs fantastic. I drive it from La.To Tx.To work every week. I have a 1992 Subaru that is, well a Subaru, but my daughter drives it all over. It has over 200,000 miles.
I guess we could get technical about production month and all but I hope this person has a depression proof job and does not end up riding a bicycle. Maybe the thought that some of us drive what we can has never entered this persons mind. Maybe sarcasm is far more fun. Maybe, just maybe, some of us do not want to pay notes on three vehicles and full coverage insurance. I personally like a paid in full vehicle, $47.00 a month insurance, and the fact that I own my vehicles and they can't be repossessed
To the question:
There's severe vibration caused by a part of the engine, transmission, or exhaust making contact with part of the body. If it was just an engine miss or something like an engine dampener the whole car might shake but not a single area like the dash and steering wheel.
There's a thought? Something is causing a serious vibration that is being transferred to the steering column that is connected at the top end to the dash frame thus causing the dash to also vibrate.
Most of the time a broken motor mount is the cause as others have stated and the engine, exhaust, or transmission is either leaning to one side or setting down too low and making contact with the frame. An exhaust hanger can be broken but it would need to be near the engine to cause such a hard vibration.