if mean you have made a quicktime video on a mac and want to play it on a windows system then you just need to download the windows version of quicktime from apple and copy the file across to the windows computer and it will play
OK as above then... if your going to be doing it regularly easiest way to transfer the vids from a mac to a windows PC is to buy a USB memory stick, if it's just a one off then write it to CD on the mac and then copy it to the windows system.