deleting in quicktime pro 7 (windows) deletes more than the selection

i am trying to use quicktime pro 7 for windows to delete sections of a .mov

i set my In point, advance using the > key and set the Out point.

I then press the Delete key and it deletes. However it has deleted quite a bit beyond than my selection.

quicktime version 7.7.6 (1680.95.31). i have tried this on windows 7 and windows 8.

Any ideas or suggestions?

Thanks in advance,

Les