Apple is no longer updating Quicktime for Windows, and at least two security vulnerabilities are known to exist in the latest version. These will not be fixed.
Removing Quicktime is straightforward.
This does not apply to Quicktime on the Mac.
If you still have .MOV files on your system, you can view them using other programs. I've been using Irfanview for years, and I'm perfectly happy with it. Apparently, Windows Media Player will play .MOV files, too.
[Added] Unknown points out, in Comments, that VLC is also quite capable.
