QuickTime .MOV locks up Win XP - usually...HELP

[Tumblemark]

This one's got me hanging. The Apple QuickTime plugin never worked with Internet Explorer, gave "didn't initialize" message. So I uninstalled Apple QT. Now I gotta view .MOV, but I hate to install QT + iTunes; and likely it wouldn't be a cure.
Problem: Usually I can open and play a .MOV using Media Player Classic or IrfanView (even with QuickTime Alternative as uninstalled as I can get it), but only using the ap's File>Open; double-clicking .MOV always causes a lockup. After a couple of short files play fine my very stable Win XP system locks up--cursor freezes, Ctl-Alt-Del doesn't work, hard reset necessary. Sometimes the first .MOV locks up, sometimes the 3rd or 4th. I've tried everything I could think of: uninstalling, reinstalling (QT Alt sometimes won't complete install on 1st try), cleaned my registry with Registry Mechanic, deleted files from \Win\system32, etc.
Also loading an .MOV into Win Media Encoder or GSpot>render always locks up, but only after the progress bar grows a bit.
Otherwise, even serious video editing, DVD backup, playing MPEG, AVI or WMV, etc is no problem with any ap; only trying to play .MOV locks my system. I'm guessing that something is missing or duplicated, but I can't figure out what. Help would be greatly appreciated.

[bazooka]

The file might be corrupted.

You do not need to install Itunes.

Just click on the free player link.