>>>(3) do not use a resolution of 1 ms. You may end up killing the system
>>
>>Killing it in what way?
>
>
>Spending resources for nothing - do you really need a 1 ms event frequence ? Will the timer event finish in 1 ms ?
>If you are inputting data in a form, say, do you want that to be interrupted a 1000 times/sec ?

Yes! Quicker would be better!! The project is a hobby application where the timer checks the input of a usb io board. The io board is connected to six phototransistors on a pinewood derby race track (Cub Scouts). There are two phototransistors per lane spaced 12" apart. The speed of the car is calculated by the elapsed time between tripping the photosensors. The timer is only on from the start of the race till all the cars cross the finish line. The computer is dedicated to doing this task.