I guess the question is why are you booting in safe mode in the first place? But anyway,
How many profiles do you have? Usually what happens is if you have more than 3 accounts, the screen size being in safe mode can't show all the accounts due to the 640x480 screen size.
I assume that the first account you see is Administrator, followed by whatever other user accounts, that you click on the icon to get to the desktop right? You should be able to use the keyboard by hitting the TAB key to move between each icon, (each icon should have a feint black border around the icon when it is highlited) Then you can use the keyboard arrow keys to go up and down to pick a different user account. If you have a scroll wheel mouse, the scroll wheel should move down the list as well.
