You can very easliy do this in the timeline mode.
Just place your clip on timeline, go to the specific frame from where you want to remove frames using the timecode field just below the monitor(or by moving your CTI)
Spli the clip using the split clip icon(shown as a scissor)
Then go to the last frame of the portion you want to delete
Split the clip again and then delete the portion.
Please Note that do not use the other scissor icon visible, as it is a smart trim tool, not a split tool.
You can hover over these icons and see what are they.
I agree with John. This IS video editing. This is what you do with Premiere Elements. And you really must do it in Timeline mode.
You do know that you can zoom in and out on specific areas of your movie (even zooming into a specific frame) by using the + and - keys, right?
If you need help with basics like this, you should check you my free 8 part Basic Training tutorials at Premiere Elements support site Muvipix.com.