Title says it all. My wife is not a huge Elder Scrolls fan, but is interested in this game. The bonus' of the Imperial Edition do not interest her so she is going to get a regular edition, whereas I am getting the Imperial Edition. Can I use my Rings of Mara to marry her while we level together? Or do we both need to have the Imperial Edition for that?

The rings are obtainable in game without buying the imperial edition, The imperial edition gives you a set so you only need one copy of the IE if you don't want to find them in game..

If Betheda has stated that the rings will be obtainable in game then it is reasonable to assume that you don't both need the imperial edition to get married.