arrangements of colour

I don't know any muslims but I'd like to know if the following cartoons are offensive. The first one is obviously pretty nasty but the second one is kinda funny. I've scrubbed out Mohammed in both of them. The point I'm trying to make is this:

Do Muslims find these cartoons offensive because they show Mohammed or because they're critical/satirical of Islam as a religion?

If they are offensive just because they show Mohammed then I can see why Muslims would get upset. But if it's for the latter reason then I really can't see why they're such a big deal. Making fun of religion is a pretty elementary thing. To me anyway.

In the words of Rowan Atkinson:

The freedom to criticise ideas – any ideas – even if they are sincerely held beliefs – is one of the fundamental freedoms of society and a law which attempts to say you can criticise or ridicule ideas as long as they are not religious ideas is a very peculiar law indeed.