If I have a windows oem cd but use the key from my technet account, does this in any way, effect the windows installation? Does this have any legal repercussions?
Well technically you would need to use OEM key for OEM version. Also there's chance that OEM version is going to refuse the key. If you do get any problems, there are tons of questions here related to that. Legally, I have no idea so I'm not going to speculate. Still even if it could be interpreted as illegal, if windows activates using technet key I wouldn't worry too much.