Some problems with your home's windows can be fixed with a few simple tools and a bit of know-how and patience. While a window repair person may be needed in certain cases, you might try a few of these simple repairs first to see if this addresses the problems you're having with your home's wood windows. Remember, however, that if your home's window has broken glass, you want to leave that repair to a professional as pieces stuck in the window frame can easily fall out when least expected. For other repairs, note the following suggestions.
If your windows get stuck, chances are the wood has simply swelled due to moisture and humidity. This can cause the wood to stick against the frame. You don't want to start sanding down various parts of the window because this can then cause gaps, and you might not address the area that is causing the sticking. Instead, start with a leveling tool and note the area where the wood seems to be bulging. Use a wood plane tool to remove some of the wood or just a light sander. Make just one or two small passes on the wood and test the window for sticking. Continue to lightly sand or just run the wood plane tool over the window frame once or twice before testing the window again, so you don't remove too much wood overall.
Wood windows are prone to rot and this often happens at the sill, where moisture collects. You don't want to just putty over this rot as the wood will continue to rot from within. Instead, tap the sill from underneath with your hammer until it comes off the window frame. Use it as a template for cutting a new sill. Use wood glue along with nails to attach the new sill into place, so it's secure. Then you can paint or stain it as needed.
Loose mortise plate
The mortise plate is the flat plate that a window lock slides into and it may be loose because the screws are simply coming undone. However, it may also be that the wood underneath it is soft. If the mortise plate for your windows are loose, unscrew it and check the condition of the wood. You may want to add a coat of wood sealer under the area of the plate to strengthen the wood, then replace the plate and screw it back into place. If it continuously comes loose, you may need longer screws to hold the plate in place.