Y'all gotta read the manuals - they are, dare I say, as enjoyable and captivating as flying this wonderous aircraft itself (well that might be a slight stretch..but only slight) There's a veratible treasure trove of information, tips, how-to's and just "plane" fascinating nuggets in there. The detailed introduction is as good a place as any to start - just getting my memory refreshed on fsx.cfg necessities was worthwhile as it's been so long since I looked in there and sure enough, somewhere over the years, several pc's and installs later my WideViewAspect setting was incorrect.
I personally enjoyed the "How to taxi like a pro" in the flight crew training manual and even discovered through the manual that I could tweak some basic aircraft settings through Ops Center - very useful since I'm at work and can't use RDP to go home and run FSX to tweak some stuff. Even reading about the equipment in the crew rest areas was educational!
So, if you're like me and stuck in the office where you can't fly - make the time pass more enjoyably by reading the manuals (whilst appearing like you're doing actual work) I gaurantee you'll find something you didn't know before or get reminded of something you long ago forgot - assuming youtube is blocked by your corporate firewalls so you can't watch these awesome tutorial videos as well. Who knows, maybe an hour spent doing this will avoid having to post something in these forums where you'll receive the customary response from the occasionally intollerable Mr. Care Bears and Pink Daisy's