whichever option you chose .. try not to lie from word go ... If you are promoting a site there should be enough content/information there that people would go there without having to lie to them. Keep in mind that people might come back to a growing site, but if you lied to get them there they might take a personal interest in making your life hell.
it's all depend actually. but it's better to be as owner. it gave you many benefits. 1. you show who you are 2.you increse your profile (post no.) 3.people knew you are active 4.you can monitor all the post content when reading it. and many more. acting like user just can do for few times coz it's easy to spot that you are faking or not. but good for starting forum. just my thought.