Re: New dojo/new student
Do you have a friend from your old dojo who could come and visit to help out with the first few classes? If I was a bit closer or could drive I'd definitely volunteer; maybe there's someone else here close enough who could be your uke for a while to get the ball rolling?
I think that two hours might be a bit too long. However, I also think that you need more than two hours to give a proper introduction to Aikido with a class of beginners only. It's not ideal either way, I think.