Misconceptions about the direction and consequences of elections in foreign countries are common. On the Guardian's comments sections, for instance, a number of Brits cling to the possibility of Geert Wilders winning next May's election, becoming prime minister and taking the Netherlands out of the EU.
While Wilders' PVV is on course to become the largest party in the House of Representatives (Tweede Kamer), he would realistically need an outright majority of 76 to rule alone. This wasn't even achievable for the Christian CDA in its heyday. Currently Wilders is topping around 36 seats in the polls which I believe is not far removed from the upper limit of what he will ever be able to achieve. Even if this upper limit is higher than I expect it to be he will never be able to form a sizeable minority government on his own. Becoming the largest party in an election also does not give one the right to supply the new prime minister for any new coalition. Add to that that all major parties have agreed not to step into a coalition with the PVV and the outcome is clear.
Wilders' will become the largest opposition faction in the Tweede Kamer, he will make more noise than ever, his supporters will feel outraged 'the will of the people' has been ignored. A coalition government of up to five or so parties, more than we have ever had, will be formed, but on the other hand this is something we Dutch are very experienced in.
It will not be us that precipitate the breakup of the EU. The only two major eurosceptic parties are the PVV and the socialist SP, and the SP is not for breaking up the union but for reforming it along more socialist lines and giving some powers back to the national parliaments.