Sorry for picking up an old thread, but thought it would be of help.
Cara72, as an owner of a Laser Tag arena I can tell you the age of 6 is the minimum allowed by insurance companies.
Generally we find the majority of 6 year olds do enjoy it, but it really depends on the individual, some 7 year olds are scared while some 5 year old could probably play without a problem. Most venues will allow your child to view the arena and make a decision if they are comfortable with playing or not. Always try on the equipment, some such as LaserQuest equipment is very heavy - too heavy in my opinion for 6 year olds, while if they use Quasar/Quasar Elite or Zone Nexus equipment they are considerably lighter and therefore should be fine for a 6 year old.
We have different lighting in our arena. Upstairs is well lit, while downstairs is darker with more lighting effects so we can cater the more nervous vs the older/braver kids and adults.
Indoor Laser Tag or as you know it, Laser Quest, is generally not intended to simulate combat. The weapons don't look in any way like a real gun, although some resemble a SiFi phaser. You have flashing lights all over the place and you fire laser beams. There is a world of terminology surrounding it in the USA, where they say Tag an opponent, rather than shoot, as they want to distance themselves from being in any way connected with firearms. The UK does not go quite as far. When you get hit generally your equipment shuts down for a few seconds and then starts up again and you're back in teh game.
Outdoor Laser Tag is very different, you generally play in paintball fields with weapons that are similar in appearance to real weapons (these vary depending on the system used). Normally played with limited lives a player with people eliminated. This generally has a minimum age of about 10, and is a small kids version of paintball. This I would regard as minor combat simulation.
Iklboo, at my venue you wouldn't be allowed to play in high heels because it isn't safe. Flat shoes are essential, and would normally recommend casual clothing as this is a physical activity. Treat it as if you were going for a country walk, with light clothing so you don't get hot.
I hope that helps, message or reply if you want to know any more.