When you're highlighting entire rows or columns in MS Excel that don't start from the top, Excel actually will let you know how many have been selected as you go. Notice 9R in the image below, indicates 9 rows have been selected.
Just highlight the range that you want (rows & columns) and look in the name box, which is to the left of the formula bar. It tells you right there how many rows & columns you have chosen, 11 rows and 5 columns in this example. As long as you're holding down the mouse button you will see this, as soon as you release it, this information will disappear.