WS.
If the engine is the original one and giving smoke then get it checked by reputable mechanic and ask for his advice. If its not repairable then you should consider swapping because it is usually the cheaper option. There are a lot of options for a swap which depends on your budget & what is it you actually want (power, economy, reliability, etc). The engine that most people opt for is d15b dual v-tec which gives good fuel consumption while giving optimum power for a daily driven car.