Turbo Trainer Advice

I've started using a new gym near my work and cried for joy when I saw two 'Watt bikes' unloved and unused in a corner.

But to be honest I've no idea what any of the figures or graphs actually mean. I've never trained to power output before.

I can push 200 Watts for an hour (what should I aim for?)
My stroke balance is fairly even but never completely 50/50% eitherway and dances between the two by a few percent.

Im producing a horrid peanut shape on my power curve.
Should I be aiming for a perfect circle - the bigger the better?

My cadence is around 100RPM - Is this a fast enough cadence?
It already feels unnatural to my normal mashing technique.

You need to read the Watt Bike training manual over here

Watts on their own are pretty meaningless without weight/HR as additional variables.

90-100 rpm is suggested to be more efficient generally but YMMV