Question about milliseconds

lets say there are two computers. One really really fast and one very very slow.

they both load up the same .swf file. If if they have preloaders would the slow computer run the .swf slower than the fast computer?

I have this button and it will not perform an action until 200milliseconds later. This is very important for an effect. would this mean that on a fast computer the action will be performed too quicky and on a slow computer too slowly?