you need to give alittle more info, such as the verison of the Operating System you are running. Since some fixes are handled differently.
click the Start, RUN
type msconfig
this will bring up the microsoft configuration utility.
to go the STARTUP tab (last tab)
look for any referrence(s) to quicktime. uncheck it.
restart computer. and it will not load again,
now each time you load QT it will admend itself and force itself to once again, take a spot in the System tray.
so do this procedure each time.
once loaded QT, look for something in the preferrences to disable the load at startup option