Go here: http://www.k-litecodecpack.com/ and download the latest QuickTime Alternative package. I'm showing 1.22, but it might be higher later.
Uninstall QuickTime and then install QuickTime Alternative making sure to install MediaPlayer Classic as well. QuickTime Alternative will install the codecs needed to play QuickTime files, and MediaPlayer Classic is a handy little (free) media player that can play QuickTime (and RealMedia) files along with any other file type that has a codec installed. It's basically a great drop in replacement for Windows Media Player with useful features lacking in Windows Media Player. Aside from it being under 1MB in size and being very resource friendly needing only between 5-20MB of memory.
Everytime I use Quicktime it restarts Quicktime task (it runs in the tray) which starts up when you restart your computer. I can shut it down with startup cop. Heres my question, is there a way to keep it from starting up in the preference?