you can resize by clicking on the image and then dragging on the "handle in the corners. This will keep it in perspective. With lines, try double clicking and then in the colors/lines tab and in the lines section select NO line

Note, Resizing/Cropping does not actually make it smaller, the original can still be reset . when you have images as soon as you click on them you should see the Picture toolbar pop up...

also

look for the Icon with the 2 XX, it is for Cropping if you want to zoom in on a portion of the image.