Your gun is likely a five shot top break chambered for .38 S&W (not the more modern .38 S&W Special). While the gun may function well, it is an antique which should not be routinely fired. It has primarily collector value which is based on the condition of the gun.
Have the gun appraised by a knowlegible gunsmith or collector.
About $400.
100-1000 USD
The worth is $539
No such model in the S&W line.
100-1000 depending on EXACTLY what you have.
No serial number given.
50-400 usd
50-475 usd
100-1000 USD or more depending on specifics.
25-2500 usd
50-2500 usd
50-400 usd