With a good spaceship you can conquer all the planets in the Solar System except Earth. amirite?

I could still conquer earth, and make you all bow down to me. And since this is the only planet that has proven life, there are people here to conquer.

Also, even assuming my ship can make the distances, the extreme heat of Mercury and venus would likely kill me before so much as even declare war, let alone conquer it.

The same can probably be said about the other side after Mars, but freezing instead. So I can conquer Mars, but I can't do much with it because as far as I'm aware, I can't breathe.

And I don't think the gas giants will be easy to land on and take over. Which is pretty annoying, because I'd totally take over Jupiter