Clash of Clans (mobile) how to attack?

I just started playing Clash of Clans for the iPhone (only level 7). My Barracks are upgraded to the point that I can train up to 30 troops, up to and including Goblins, and my Army Camp can hold up to 30 troops at once.

My main questions are:
1) Is there a way to make these idiots attack the GUNS first?! They get taken out while they're wasting their time with the buildings.

2) How many of each (warriors, archers, goblins) would be the best combo when I can only have up to 30 troops? The archers do ground and air, but I'm not yet fighting camps that have air defenders (I don't think). Warriors and goblins only attack ground.

3) I've been deploying the troops all together in one spot, because it seems when I divide and come from different areas, they just die faster. Am I deploying them with the best strategy?

Thanks! I'm mostly an RPG and simulation player, so combat strategy is still kinda new to me, lol.

1). Once you unlock Giants in your barracks, they will attack guns (any defenses) first. There's no way to force troops to attack a certain type of thing.

2). Personally I do half archers and half goblins. That works really well for me, but I also have a lot more troops.

3). Deploying them all in the same spot is probably best at the stage you are in now. You could also just deploy them all on one side of the camp you are attacking. Since archers are long range you can set them near any defenses that are close enough for them to hit. Once you start unlocking more troops in your barracks, you will change your strategy based on the different things they specialize in.

Get giants

A little off-topic, but there's a site called Points2Shop. You basically play games and watch videos for points which you can use to spend on iTunes Gift codes, which you can use to get free gems in Clash of Clans. I'll attach the sign-up link & proof it works below.

http://www.points2shop.com?ref=uin1403208874