Depends on your countries/states laws.
In the UK, it is illegal, however many people use them. Off road bulbs are only supposed to be used off road. Driving on public highways usually requires certified bulbs no darker than "ice" shades.
You should be fine with any vehicle replacing the bulbs. You can remove the old bulb and read what voltage and wattage it is to get a suitable replacement.
The small bulbs in the air-condition buttons of a 2001 Nissan Altima are referred to as parking lamps.
yes, it can be used - single phase voltage of 230v. 50HZ is important
H1 size Bulbs
no
Try the fuse and then the bulbs.
The actual bulbs; yes. The headlight housings; I don't know. For bulb information, see sources and related links below.
faulty switch
Either you're using bulbs that are stronger than the recommended rating, or you have some damage on the wiring loom causing the lamp feeds to short against the chassi ground.
(not sure if true or not) light bulbs can damage your eyes.
NO
Unless your Altima suffered body damage, you won't likely want to replace the entire light fixture. To replace a blown lightbulb in your taillight you have to access it from the trunk. Inside the trunk you will see an access panel for both tail lights. Remove the applicable panel and swap the bulbs out. Typical bulb installation involves the twisting (clockwise and the counter-clockwise) of the bulb 90 degrees when removing and then replacing it. Good luck!
By killing yourself and causing a huge lollercoaster.