iPad mini to make educational presentations

I make presentations to small groups in a community centre using internet web sites, Quicktime video and Keynote presentations. I am using a three year old 21 inch iMac which can do all these things but is difficult to carry to the centre, its a five mile walk from the train station.

I have wondered if the new iPad mini (rather than buy a Powerbook laptop which is too expensive for me) could do these presentations. I connect the iMac to either a projector, TV or colour monitor, and also to a small audio speaker.

Can the iPad mini do all of this for me?

The spec of the iPad shows the only data output connector is a "Lightning", what does this do, what can it connect to?

Thanks for your time.