I hear puppies on a rope work wonderfully as well. Not sure why the spider wasn't firing at your miner, as the main condition is that the spider must be hostile to its target. So a wild GCS will be hostile to your fort (and its animals), while a tamed GCS will need a goblin or some other wild animal. GCS don't always attack your civilians though, so maybe you needed the military personal (or again, try a wild animal) for it to properly register as "hostile."
As for what to do about the others? I use my cavern meat as animal training-trainers. Whenever I get too many/need some food (or bones/leather) I'll take the most trained ones to the butcher. If you don't need the meat, you can try encouraging pet ownership. Pasture the more tame ones in your dining room AND OVERLAY THAT PASTURE WITH AN ANIMAL TRAINING ZONE. You also need your animal trainer(s) to have NO OTHER LABOURS. The last thing you want is a rampaging elk bird in your dining room. They are more than capable of killing your unarmed craftsdorfs. That being said, if you lack military-grade metals and/or don't have a military yet... you can use them as a military force. No, you can't have "war-elk birds," but you can "pasture" tamed elk birds in front of your fortress to greet the goblins. I've used a menagerie of half-tamed cavern beasties to fend off early goblin attacks more than once. Oh... about 3 elk birds, a giant toad, a pair of cave crocs, and a GCS made -very- short work out of a goblin squad without much losses.
You cannot train the trolls at all, but they should be hostile to goblins. They can be fodder if you place them in a cage outside your fortress, and release them as the goblins (or hippies) are passing by. Re-capturing survivors will be its own issue. Personally, I prefer to use the non-tameable (and thus butcherable) cavern beasties as live-training for your military. Station your squad nearby and release the troll (usually via pitting from above) and let your dorfs get to work. So long as you keep the squads low, they'll actually get some training in (10 dorfs make short work of a single troll), and the occasional lite injury can give your doctor something to do. Everything is a resource in DF :p