Would the OEM keys on the side of the cases work with this ISO? I can't help but think not, because they're Dells, and Dell (was) in bed with Microsoft and stuff.
Last time I tried, no it does not work. The Dell OEM install is keyed to something in the BIOS, and the keys are specific to this kind of actvation checking. You might get luckly though and find it's an OEM image from dell your downloading.