Flight planning

How do you get precise when flying in FS2004? I mean on time. The NAVIGATION LOG in the flight planner always tells you how long will your flight be but he calculates it only with cruise speed. In aircraft like a Cessna 172 I lose much time on climbing. I cannot know how much time I will spend on climbing. Also sometimes I wan't to fly slower than the navigation logs tells me to.
So how do you:
1. Determine the taxi start? On big airports you can lose minutes on taxiing.
2. I probably need ground speed for calculations but for ground speed I first need TAS, right? So how can I calculate true airspeed on a given altitude? There are some heavy formulas on wikipedia but is there an easier way?
3. How can I adjust the airspeed indicator to show me TAS? I don't mean on changing the Realism settings, I mean on the little knob which is for adjusting the TAS indicator but what should I do with it?
4. Calculate needed fuel? There's no need to go on a trip with full fuel tanks if need only half of it. I found information on wikipedia about different engines and fuel consumption but that depends on altitude and power settings.
5. What's the best cruise altitude for piston engine aircraft?
6. How can I plan my descent? I only know to plan my descent if I know how much minutes I wan't to descent. If I wan't to descent 3000 feet in 2 minutes I will start descending with a rate of 1500 fpm. But what if I don't know the time but I know the range I wan't to descend? For example if I wan't to descend 3000 feet in 5 nm how can I calculate this?
7. For ground speed calculations I need wind information and some airports don't have ATIS, and the ATC doesn't tell me so how can I get the wind information?
So how do you:
1. Determine the taxi start? On big airports you can lose minutes on taxiing.
2. I probably need ground speed for calculations but for ground speed I first need TAS, right? So how can I calculate true airspeed on a given altitude? There are some heavy formulas on wikipedia but is there an easier way?
3. How can I adjust the airspeed indicator to show me TAS? I don't mean on changing the Realism settings, I mean on the little knob which is for adjusting the TAS indicator but what should I do with it?
4. Calculate needed fuel? There's no need to go on a trip with full fuel tanks if need only half of it. I found information on wikipedia about different engines and fuel consumption but that depends on altitude and power settings.
5. What's the best cruise altitude for piston engine aircraft?
6. How can I plan my descent? I only know to plan my descent if I know how much minutes I wan't to descent. If I wan't to descent 3000 feet in 2 minutes I will start descending with a rate of 1500 fpm. But what if I don't know the time but I know the range I wan't to descend? For example if I wan't to descend 3000 feet in 5 nm how can I calculate this?
7. For ground speed calculations I need wind information and some airports don't have ATIS, and the ATC doesn't tell me so how can I get the wind information?