A proper engine rebuild is anywhere from $1,000 to $2,000. Dropping in a remanufactured engine is about the same cost, and a proper engine rebuilder will have more consistent results.
You might be happier with the 2002 if you just take the advice of the people in this group and set the HVAC controls properly.
Maybe an explanation of how the car's interior heating system works would help. The heater core is basically a mini version of the radiator at the front of the car. Coolant flows through the radiator or heater core, and it gives up heat to the air flowing past it.
Something to keep in mind is that if the car has been sitting out in the cold and the engine coolant temperature gauge is showing that the coolant is cold, you won't get any heat no matter what you set the HVAC controls at. Interior heat comes from air blowing past the heater core, and the heater core gets its heat from the engine coolant. If the coolant has not warmed up and you have the fan speed set on high, it will take longer to heat up the engine coolant and so it will take longer to heat up the car.
Do this: When you first start the car, keep the HVAC fan speed on the lowest setting until the engine coolant temperature gauge starts to rise, which indicates that the coolant is starting to warm up. This way, the coolant will warm up more quickly and ultimately warm the interior more quickly.
The other issue for you to consider is that moisture will build up inside the passenger compartment with the air set to recirculate because the occupants' breath contains moisture. On a cold day, the moisture condenses on the windows, make them get fogged up. You have previously mentioned that you set the controls to recirculate to reduce the intake of the smoggy air, so you have 3 options to reduce or eliminate the fog.
1) Accept that the AC comes on when you set the controls to the front defog mode because the AC will dehumidify the air if ambient temps are above freezing and just set the temperature to a warmer level - IMO, this is the best option for you because it allows you to leave the air intake on recirc mode. 2) Set the air intake to the fresh mode - this is the best option for people who don't mind breathing the air outside the passenger cabin. 3) Get a Ford product that has the Insta-clear front window defogging system. The Insta-clear (not sure if this is the actual name of the system) has a very thin layer of electrically conductive material on the inside of the windshield, giving it a gold tint. When activated, the conductive material heats up with the same principle as the read defogger so moisture doesn't condense on it. The downside to this option is that replacement windshields are very expensive due to the coating, and you can't place any stickers on the interior of the windshield because scraping the stickers off will damage the coating.