Quicktime will not work or uninstall

Running Windows XP Home SP2
In trying to use Quicktime I get the following: "buffer overrun detected. A buffer overrun has been detected which has corrupted the program's internal state. The program cannot safely continue execution and must now be terminated"
I tried to uninstall and get a "Fatal install error". So I tried to reinstall, and the install completed successfully, but the program still will not work, giving the same message. I'd like to uninstall and install QT Alternative.
How do I uninstall a program that will not uninstall through normal uninstall procedures?