Re: New to motorized bikes.
I think either of the two mentioned bikes will do what you want. I'm a 4-stroke guy, myself, so I can't say either way on the engines. I'm sure that either would be fine. My first 3 bikes were all beach cruisers. I ended up with a stretched cruiser and will probably not have anything else. I don't go off-road either. If you prefer a mountain bike, there are some available but the newer mountain bikes with full suspension can be tricky, from what I've seen. You can do a rack mount with this type of bike and have an engine over the rear tire.
Caution! I give opinions as if they were worth something. Use at your own risk.