What computer operating system is your Premiere Elements 10 running on? For now I will assume Windows 7, 8, or 8.1 64 bit.
After you apply the Crop Effect (Edit Header/Effects/Video Effects/Transform/Crop), you click on "Edit Effects" toward the bottom of the Effects area to bring up the Properties Palette for that particular clip to which you have applied the Crop Effect. You should see
Adjust the Crop sliders accordingly.
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