I have a manual thermostat with two wires and I would like to connect a programmable thermostat which has four connections. I do not have AC. So how do I hook up a four connection programmable thermostat to a two wire connection.

As long as the thermostat doesn't require a common to power itself, just connect one wire to R or RH, and the other to W. RC and Y are for A/C, and G if for fan on.