Yes, charging to use roads would decrease the congestion problem, because whenever the price goes up for something, less people want to use it. If driving becomes expensive, people will look for alternative measures to travel. A government considering this will need to have a strong system of public transportation in order to accommodate alternative means of travel.
Charging to drive on highways doesn't cure congestion problems. People who want to drive on highways, bridges or tunnels will do so no matter what. The way to reduce auto traffic is to have better mass transit systems. Faster trains, more efficient buses and better routes to population centers are all needed as part of an overall strategy to alleviate traffic problems.