"How can you even compare holocaust denial laws to what muslim countries do?" - Very easily. The holocaust was over 65 years ago. The perpetrators of this egregious act are mostly dead. The victims of this egregious act are mostly dead. The modern German of today had nothing to do with the holocaust. Their mother and father had nothing to do with the holocaust. What does making holocaust denial do other than prohibit a form of dissent? Does it bring people back to life? No, it does not. Does it stop it from happening again? Just because a crime is unmentionable does not mean that it would not happen (and the holocaust is not the only genocide, nor the most efficient one, there have been many more before and since).
When you remove the right to say fuck, you remove the right to say fuck the government. In Germany any debate on the extent of the holocaust is stifled due to the law, the same (but opposite case) as it is in Turkey with respect to the atrocities referred to by some as the Armenian Genocide. In both cases the law is wrong and stifles free speech and people go to jail[1][2] for dissent against it.
> Religious headscarves should be banned for the same reason slavery is.
You really have no understanding of the purpose, origin or practice of the headscarf in countries around the middle-east and mediterranean whatsoever. Would it come as some surprise to you to know that in the early 20th century Irish women would wear headscarves to protect their modesty? Oh those poor oppressed Irish women, whatever became of them?
[1] - http://www.rense.com/general78/dsdde.htm
[2] - http://news.bbc.co.uk/1/hi/4205708.stm (although in this case one of Turkey's most celebrated authors' trials was cancelled at the last minute)