will backups of these games work okay?

[ClareJ7]

Basically, the shop 'game' in the UK are selling new super mario bros for £34.

but if you trade in one of the following games you get £20 off

mario party 8
animal crossing
mario kart
super mario galaxy

luckily ive got all the actual copies of all of these, so im thinking i'll get rid of one then just download it back again.

Im thinking of getting rid of galaxy, do backups of these games work okay? no security thing on them or anything?