Rocketman, I think it was actually courageous to step into a Christian church by yourself. Did you feel real strange, out of place, wondering what might happen to you there?
I was raised a Lutheran, and you gave a pretty fair assessment. That's a good place for a first encounter. Realize that other denominations will do things differently--music, sermon guidelines, procedure, etc.
As for what you said about the music, most mainline denominations use hymnals and it may seem a little dry. If you go to an independent, or non-denominational church, most use contemporary music with regular band instruments, and the music is displayed from an overhead projector or is in the worship bulletin. It's more lively, with people clapping to the music or lifting hands. The pastors wear casual clothes. If you have a chance to attend a Calvary Chapel, you'll get an idea. These churches want to appeal to people who have been turned off by "traditional" churches.
Most churches take offerings during the service. Don't feel obligated to give. The pastor of the church I attend even tells visitors not to give, so they won't get the impression that churches just want money. I've even been to a successful church that doesn't set aside a time for offering and the pastor doesn't even mention anything about it--ushers stand at the back with bags in case people want to drop something in on the way out.
More JWs, Mormans, and atheists should take time to explore what a good church can be like. They might be surprised.
I'm just glad you didn't decide to go to a Pentecostal or charismatic word church, where the whole congregation starts speaking in tongues during the service. You may have been scared off permanently.