No need to worry, daft is fine...
Zenon headlights come on slightly dull and then brighten up over a matter of seconds. In addition the beams will drop down automatically and tilt back up again once they have found the reference level. They have to be self leveling to comply with the law. By now they are at full brightness, which is much whiter and brighter than halogen lights.
Halogen lights by contrast, come on a full brightness but are not as bright as zenons, and the beams don't move down and back up again.
If you look at the head lights from the outside, the zenons have a thick magnifying type lens in them and the halogens look conventional with a ribbed silvered reflector and a bulb clearly seen behind a clear plastic lens.
Hope that helps.
Alan