How to trim imovie?

Hi,

This is my very first time to use QuickTime Player to record a quick movie. It did a job. Now, I noticed part of it pausing (waiting) is a bit long, and it's somewhere in the 5 to 8th frames of the movie, I noticed the Trim function for the Edit, so, I tried it, thought it allows you to select a Start and then Stop for Trim, but it does not appear to work this way. Searching for help on that, got a youtube video, saying selecting starting and ending point would save everything in between, it does not serve my purpose. Then, somewhere else mentioned about Crop, but I don't see the Crop function. So, how do I remove these frames?

Btw, I don't see QT version, hence, couldn't post it but my Mac OS X is 10.6.8 (don't laugh, I bought for testing purpose several moths ago).

Thanks.