How do I restore my 2nd gen itouch when its in DFU mode?

the problem im having is the itouch keeps showing a white screen. i can still unlock and and listen to music but it just shows a white screen. ive tried restoring it and it doesnt work. and i tried pressing teh home and power on. so now im putting it in dfu mode but when i plug it in before i press restore i have to push down on shift and click restore. but what do i choose for that?