In order to achieve the ''Survive an Arcade level using nothing but the flashlight and handheld flares'' achievement the fastest and the most sure way you will have to start an arcade level ,better in low difficulty so that only 2 takens will hunt you . So all you have to do is to spot their positions .When that is done you will only have to run in the opposite direction .Be careful takens will probably run and catch up to you ,but when you feel their breath on your back you can simply right click to them with the flashlight on them , they will stop for a brief period of time and you can keep running (with shift).
You can also use some flares to win sometime but nothing more .All you have to do is to keep AA+lan safe for 10 minutes .After that the achievement is earned...
Pretty easy ain't it ?