Well, there is unconfirmed story that in 1933 Poland secretly made a proposal to French goverment to start a preventive war against Germany, since Hitler had started remilitarization of the country. The French refused and that was it.
I do not think that Poles by themselves would have started such a war. While German forces were still weaker that Polish Army at that time, Germany was much bigger and with much more powerful industry. They could have easily mobilized much bigger forces full of WWI veterans and eager youth. Reichswehr would have given a good, professional cadre for all those new units. Also, Poles couldn't have sent all their army against Germany, they also had Soviet Union on their eastern border.
Another problem would have been German fortifications in the east - Poles had very little of heavy artillery to deal with them.
And another thing - Poland would have had enormous logistical problems fighint such a war. Poland simply couldn't have afforded it.
Not to mention political uproar such a war would have caused - all against Poland. Piłsudski knew that well, he would have never agreed to do it. He wasn't stupid, you know.
But let's assume he was that stupid, or got crazy, or something like that. Poland sends 25 divisions against Germany (15 stay to keep SU at bay and guard the country against German counterattacks). Where? Silesia and East Prussia were well fortified. March straight to Berlin? With flanks exposed? No, thanks.
Honestly, Poles were unable to become serious threat to Germany on their own. Together with France (and UK) yes, as a second front, dangerously close to Berlin and Silesia. But alone? No way.
However, there is a possibility of a border conflict - occupying Gdańsk/Danzig, some part of Silesia, something like that. But even that would have been a political suicide for Poland. Poles would have been seen as dangerous militarists and warmongers. Such an action would have destroyed Polish-French alliance, which was very important to Poland.