(1) if light intensity increases as you increase the current (throttle) to the train
(2) can you provide enough power to the train to have the lights go on but not have the train move (or barely move)
(1) Yes
(2) Not usually. Typically the motor will begin turning before the lights get enough juice to light up.
You might be interested in one of Tomix's throttles with "CL" (Constant Lighting). THese throttles use some kind of high frequency AC signal that is capable of turning on lights without triggering train movement. They don't work with all lights: Only Tomix trains that have the "CL" logo on the package (looks like a front view of a train with headlights and "CL" written underneath) and many recent offerings from Kato and Micro Ace (no package labeling for CL support). The throttle has two controls: One for lights, and one for movement.
I don't have one of these throttles, so someone else here could likely say more about their effectiveness.
Another solution is to go DCC, but that may be more complex than you are interested in.
But with a regular powerpack, the train will be moving before the lights work; and moving at top speed before the lights work at full brightness.
