It's a little pearlscale! How incredibly adorable! <3
And the ranchu, well, I think it's a completely normal one since his fins don't seem particularly elongated, and his headgrowth doesn't seem to have the shape of a lionchu
But I'm not that much into the subject, I more or less know the basics about the different ranchus :'D

btw, that's me. i forgot to login to my account. what a noob >_>

Hey! (:
It's not good to have food laying around... maybe you should either try feeding less and more often, or simply try another kind of pellet? There are those that sink a bit slower in case you're noticing that the fish are having a hard time seeing the food and that's why it's left! Because it's not healthy at all for the fish to leave uneaten food until those "worm organisms" show up to deal with it. That's definitely a sign of over feeding! Just put a small, small amount of food into your tank and stop as soon as you notice that your fish aren't interested.

But then about the headgrowth, it varies from fish to fish how big it grows, but if you will want it to grow more you could try a more protein rich diet for your fish! You could try feeding some frozen or freeze-dried blood worms, tubifex or krill! The fish love it, and it's only healthy for them This is very good for all of your fish, especially when they're young, and it will let them develop more beautiful bodies and be healthier (:

There are lots of threads on this forum about goldfish feeding methods, you could try looking there!

and oh sorry about my not-so-perfect English.. English is my secondary language 

Sorry I cannot help to identify the types of fish, as we've been in fish keeping now for 10 weeks only or so.
But I agree with Nossie: please do not feed to much. Left over food will rot and disturb the cycle in your tank which can lead to sick fish. Please feed less. We do feed our goldfish twice a day and only what they can eat in 2 minutes.

And your English is beautiful... it is my second language too 

Hanna:: I didn't know! Aren't you from Australia? So what's your primary language? (: (Mine's Swedish)

Vann:: Good (:

I am not from Sweden, though ;P I just live in Finland by the coast where we speak pretty much of Swedish d:
And I have no idea who this person is! xD

Oh, that's quite interesting! (:

Those fishies of yours seem to be getting more and more... hungry xD

I have a rly good book with some of the more common pests in aquaria, such as algae, snails, worms in the water... it's a very good book (: Called "Manual of fish health" or something like it, you should try checking it out! The pics in it are great!