Are there cheeses that are not suitable for making for macaroni and cheese?
I can think of three general reasons why some cheeses are better than others for melting:

Age:
The age of a cheese often determines how well it'll melt.  For instance, a 5 year old cheddar will (generally) not melt very well into a bechamel sauce.  

Texture:
You may find that stringy cheeses like mozzarella make the mac'n'cheese more difficult to eat, as it's a little impractical to have strands of cheese hanging from your spoon.  At the same time, cheeses like parmesan or feta may not melt the way you'd expect for a cheese sauce

Taste:
As for flavour .. I don't think many people would line up for macaroni and blue cheese :o