Don't burn logs and coal at the same time as the moisture from the logs sticks the ash from the coal to the chimney so it will need cleaning more often.
A fire is like a child you need to nurture it and feed it, start of with newspaper scrunched up and fine kindling, then add bigger thicker pieces till you can chuck on split logs, mix wetter and dryer logs to keep it burning well as all dry wood will just burn up quickly.
For coal I find laying one deep on the bottom and using a one solid fire lighter on top then build up around it works well, you can almost light it and walk away.
Coal will give more radiant heat where as log heat will go up the chimney, I think you loose 80% of your heat up the chimney so think about a log burner which only chuck 20% up the chimney. Also don't bother lighting a fire at 6pm when you come in, by the time your going to bed it will just about be kicking out heat, it takes a while for the chimney, hearth and surround to heat up then it will radiate into the room.
We keep our ticking over in the winter at weekends by closing off the air vents and chucking a log in every other hour then open them all up and fuel it up.