I don't know if these are perfect translations or not.

Catapultam habeo. Nisi pecuniam omnem mihi dabis, ad caput tuum saxum immane mittam.
I have a catapult. Give me all the money, or I will fling an enormous rock at your head.

Latine loqui coactus sum.
I have this compulsion to speak Latin.

In dentibus acticis frustrum magnum spinaciae habes.
You have a big piece of spinach in your teeth.

Antiquis temporibus, nati tibi similes in rupibus ventosissimis exponebantur ad necem.
In the good old days, children like you were left to perish on windswept crags.

This is The Agent speaking...

Catapultam habeo. Nisi pecuniam omnem mihi dabis, ad caput tuum saxum immane mittam.
I have a catapult. Give me all the money, or I will fling an enormous rock at your head.

I thought that's what that one said, but I though you'd maybe put more of a hidden meaing in it....guess I was wrong.  

I'd like to see you try and catapult a rock at my head.

*runs and hides*