Should I replace old wooden siding with brick?
Adding a brick facade to the lower front of your house may not be as easy as you may think. Your contractor may have issues with installing a footing to support the weight and proper backing to attach the brick ties, not to mention building out all the window and door jams to match the new depth.  This could be a very expensive change. 

As far as adding value; value is in the eyes of the beholder when it comes to cosmetic choices. A brick veneer will not have the same value as a structural brick wall. Exterior sidings do not command as much value as a new bathroom or kitchen would. The question you have to ask yourself is, "Would a new buyer want to spend the additional $$$ on a brick veneer as opposed to traditional matching siding?" Don't get me wrong, curb appeal is very important, but the style of siding is rarely the "WOW" factor that drives a substantial increased value. Having a clean and neat exterior appearance is the first step in getting folks to walk through the front door with a positive attitude. What people see the first minute once in the door makes all the difference with perceived value.