"Given my usage pattern - what is the best way to conserve the battery?"
You'll need to re-write that to define what conserve means. It could me how to prolong the run time or make it last longer in storage. Since these have been discussed in "discussions that never die" here's the short answers to both. To prolong the run time, dim the screen, turn off wifi if you don't need it, unplug that USB hard drive and printer. To store the battery, charge it up (yes some say 40% but let's make it easy) and then put it in a air tight bag with desiccant and put it in some fridge (Non freezing, just cold.)
"Will netbooks/laptops work under external power if the battery is removed?"
All do so far.
"If I store the netbook/laptop in the closet, should the battery be removed?"
Not a bad idea. Still like to see air tight bag and desiccant for both devices.
Bob
I will not be buying a netbook or laptop for regular portability. It will be for use during a move until I get around to buying a new desktop.( Using T-Mobil webConnect I guess.) It will then become a backup computer or for rare portable use.
Given my usage pattern - what is the best way to conserve the battery? Will netbooks/laptops work under external power if the battery is removed? If I store the netbook/laptop in the closet, should the battery be removed?
Thank in advance
Jack
NOTE I posted this under buying advice because I don't know if all models work the same way.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic