HDloader - will it play CD games ?

Hi all,
I am using winhiip (great program)to put games on hard drive only done DVD games so far. have ready up but see confusing information.
Can I load CD games ?
Do I need to covert them to Image files ?
is there a minimum size the game must be to work ?

Pretty sure I need to covert to image file which is no problem but some post suggest not all cd games will work and need to be above a certain size?

Thanks Alan