I'm not sure what his problem is. Some times kids are anxious at bed time, worrying about monsters, etc. Many kids just have the active brain he's talking about where his thoughts rush around in his head. One suggestion I would make you may not have already tried is to use lotion to massage his arms, legs, and back. In a way it has a similar effect to holding him down, but is more nurturing.
Another idea is to play the quiet game. His older brother can join in as well. It's simply that who ever is quiet the longest wins. You could have a small prize the next day as a reward for the winner. The same could be done with the one who keeps their eyes closed the longest or falls asleep soonest.
His talking back more lately may be related to feeling angry about being held down or whatever methods your husband uses to force him to stay in bed.
Thank you. I'll try those suggestions. As far as his being angry, I'm not sure. My husband doesn't have to hold him down, I do. My husband's voice is strong enough that my son will lay down for him. I'm the one that mostly has trouble with him. Sometimes it takes me 2 hours to get him to sleep, and I have had to move him to my room so that his brother can fall asleep at a reasonable hour. And usually, he's a happy go lucky guy the next day, as if the previous night I hadn't had all this trouble from him. I know he tests how far he can go with us, but it's getting frustrating.
My husband was diagnosed as ADD as a child, and I asked my son's preschool teacher if she though he was too, but she just said he's extremely intelligent, and needs to be kept interested.