Head removal (noob) question

I'm considering taking my heads off to have them checked out / freshened up. They are on my 360, still on an engine stand. After taking off the intake manifold, I can see what appears to me like a fair amount of carbon build up on the intake valves. It's kinda hard to see in there, but it's got a build up.

Is this anything to be concerned with? The engine is a reman with around 26k miles on it.

So if it is suggested to take off the heads, is it a very difficult thing to do? I have some decent tools, and torque wrenches. Or will I be opening a can o' worms due to the fact I've never done this before, and will I need to mess with the rocker arms? Can the heads be re-assembled and set up by the machine shop, so that I can just bolt em on with new gaskets?