help

So Tucker is now 9 months old and has entered the stage of tantrums. I am going to rant for a few minutes and anyone that has had children do this....please give me some advice. For the past week Tucker throws HUGE screaming/crying/kicking fits when it is naptime or bed time or diaper changing time or getting dressed. He absolutely freaks out. Last night we let him cry for three hours going in and trying to calm him but he wouldnt calm down and finally my husband at 2 in the morning took him for a stroller ride around until he fell asleep. Now he is screaming once again in his crib after Sean held him for 45 minutes screaming for a nap and he just wont calm down. I honestly dont know what to do.
Are we supposed to discipline a 9 month old? Do we leave him in the room or hold him while he cries? He cries until he throws up and is just a wreck. We can only hold him for so long before it really starts to get to us and we have to leave the situation. And we dont think he is in pain because as soon as he gets what he wants he stops crying.
So we havent slept in awhile and are desperate for help. We just dont want to take him on a walk before putting him down because then he will fall into a bad habit and we will kick ourselves for it.

What to do ??????