You can see a YouTube video of the message Wilders played on Dutch television (2 minutes, 44 seconds long) here: Video Muhammad Cartoons - Geert Wilders (English subtitles).
Here's what Geert Wilders says in the video:
A few weeks ago, I was in Garland, Texas, at a conference and an exhibition of Muhammad cartoons. Shortly after I had spoken, a terrorist attack took place. Islam and the terrorists do not want us to show these cartoons. But terror and violence must never defeat freedom of speech. That is exactly the reason why we should do what the terrorists want to prevent us from doing.
I asked the Board of the Dutch Parliament if I could show the cartoons in their building. They refused. And yet it is very important that we show them. That is the only way to assure that the terrorists do not defeat freedom of speech. That is why I show them to you today.
"You can't draw me," says Muhammad.
"That's why I draw you," says Bosch Fawstin, the winner of the cartoon contest.
That says it all.
What is not allowed by Islam and by the violence of terrorists, we will do anyway.
And we call that: Freedom of speech.
I do not broadcast the cartoons to provoke; I do it because we have to show that we stand for freedom of speech and that we will never surrender to violence. Freedom is our birthright. Freedom of speech must always prevail over violence and terror.