Replace Halogen spot light

I think you will find that the bezel (the outer chrome trim ring) is attached to the locking mounting rods.(the coiled wire on outside of fixture) You may need to open those rods, pull them up to 90degrees or more to the fixture and push them into the fixture body and the bezel will drop as the rods go in. It may also be connected to the bulb socket as well.

A 42W bulb is only going to produce 42 Watts of heat (well, a little less since some of the energy escapes as light (roughly 3 - 5% for a halogen)).

So as long as the fixture is rated for at least 42 watts, that bulb will be fine. The max wattage limit should be noted on the fixture somewhere, either on a sticker, or embossed in the metal.

I think your fear of the word "halogen" comes from the number of accidents attributable to 300W and 500W halogen floor lamps with exposed bulbs, these concerns have been mostly addressed with new safety features (primary guards over the bulbs). But a 42W replacement bulb doesn't pose the same hazard.