SC2Mapster

If you want to use the cutscene editor, I made a tutorial here. That might help teach you the basics of animating models and handling cameras.

Quote from totalysharky: Go

Ahh making a cutscene is more difficult than I thought it would be.

Okay, here's the deal. You can make a cutscene in two different ways- Triggers, or the cutscene editor. Triggers were how cutscenes were made before the cutscene editor was released a few months ago. The cutscene editor is much more powerful but it's also a lot more complicated. And as strange as it might sound, I'm actually going to recommend triggers for this one because they'll be easier with attacking & unburrowing. Here's the gist of what you'll want to do:

First, open the terrain editor (F4 is the shortcut, I think). Press the U key to open the units tab, select the marine, and put it down. Then select a burrowed zergling, and place those down in the circle you wanted (and make sure to set the player to 2 for those so they'll attack the marine). Next, press the C key to open the cameras panel. Hold down the control key and use right mouse to change the camera angle until you get one you like, then press "create camera". You're going to want to create all the cameras you may need. So just make a zoomed in one and a zoomed out one

Next, open the trigger editor (F5 is the shortcut, I believe). On the left side you'll see a trigger called "Melee Initialization". Select that, and then in the right panel, delete all the things underneath the "actions catagory" (leave the event called 'Melee Initilization'). Now, whichever actions you put in the actions section will happen as soon as the map starts. Here's what you may want to do.

Enable/Disable Cinematic mode for player (1) // This turns on the cinimatic mode, hiding the UI and turning off player control. It has to be on. 
Apply Camera Object (Your 1st camera) for player (1) over (0) seconds //We want to leave the time here as 0 so it starts the cutscene here. You can apply camera shots over a few seconds if you want to move to a camera slowly instead of jumping instantly

// Now you can use "Issue order to Unit" to make the zerglings unburrow or attack, or move the marine around
//"Send Actor Message to unit" is what you're going to want to make the marine dance. It's a little tricky and I dont have time to explain all of it right now, but you want to order the marine to 'Play Animation' and then set the animation to 'Dance'. If you have trouble, let me know, and I'll send you a screenshot later

//You can use "Pick each unit" to order ALL your zerglings at once. Here's how you'll use it. 
Pick each unit in unit group (Units (zerglings) in region (entire map) matching conditions(none) and do actions
{
Issue order to unit (picked unit) to (whatever order you want)
}

Hopefully that can at least get you started- I'm writing this real quick before I go to bed so I don't have time to make screenshots or anything :P Feel free to send me a PM if you have any specific problems and I'll do my best to help.