I'll answer the second.  Normally you start it 2,1 (right, left) in a two-engine aircraft.  Hit E+2, and crack the throttle.  Hold ctrl+shift, and keep you finger hovering over the F4 button.  When ready, use your other hand to press and HOLD the Right engine starter switch on START.  Watch N1 and N2.  Make sure that N1 is increasing as N2 is increasing.  In general, you want to hit F4 (which will open the fuel valve) when N2 is at 21%.  Repeat for engine 1.  Hope that wasn't confusing.

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In FS, N2 doesn't reach 25% before spooling down. You'll need to charge it at 21%.

Ya in reality, just hold the start switch, watch the N₂ begin to rise, then the N₁, wait 'til 20-25 or so (in modern turbofans, you have a wide range that will work), flip the fuel on, and she'll spool right up.

You use the subscript and supscript buttons.  4 from the right bottom row on the 'add yabbc tags'

Thanks for that info guys!

beefhole: the 3 spool engine you are refering to is some Rolls Royce, right? (Someone told me that a rolls royce has N₁, N₂ and N₃!)
Vic

Correct Vic.

The tripple spool engine is has an N3 stage, and that stage is the High pressure compressor, whereas the N2 is the intermediate stage compressor. All spools ar each driven by their own turbine and connection shafts.

Advantage compared to twin-spool engines are that the N1 fan can have a wider chord because it is not restricted to any connection to booster conpressors-
This allows for a very large frontal area and the N1 can be driven closer to its optimal speed

The actual fan - which works more like a shrouded prop - is responsible for approx 75% of the engine's thrust in the form of bypass airflow to the atmosphere via the engines bypass ducts behind the fan.

The air that flows thru the N2 and N3 compressors becomes highly compressed , of which 1/3 is used for combustion and 2/3 for internal engine cooling.

And yes I have a poster of the RB211 on my wall 

Look no further than the L1011. 
I believe the gauges are arranged as EPR, N1, TGT, N3 and FF

Any RR engine has the full three-spools layout. Fuel burn isn't an issue from what I have seen, though some pilots claim the RRs put out less power and it takes more time for them to spool up (not an incredibly noticeable amount to anyone but a pilot).

Not to say your all wrong... ive never worked on a turbofan engine myself... I have taken apart Allison 250 engines and Pratt Whitney PT6 engines, but from what ive come across, N1 has always been noted as the compressor (no matter how many stages, or whether it has a combination of centrifugal and axial compressors), and N2 is your power turbine or free turbine, doesnt matter how many spools you have...  Or in pratt whitney, they are NG and NF respectively.  I dont think they actually use the fan for a measurement, i could be wrong... but the point of where your air gets compressed is really a function of your compressors...  How much you get out of it is a function of your turbine. 

And yes, the Trents have been a favored engine in efficiency... well most asian airlines prefer the Trent.