I am wondering whether I travel in EU countries with my Belgium ID card I just received or my American passport? A little confused on information I have been given. I want to be able to travel with my spouse. Any input would be greatly appreciated.

If you have the orange 'asylum seekers' residence permit, take it with you, but don't show it, unless the person asking for it doesn't read Dutch. That one does not allow you to leave or reenter Belgium. Now, before you panic, that is the one given to most, if not all of us, whose spouse has the work permit. Instead, take your passport, and you should have no problem. After 1 year, you should be given the white residence permit, which you can keep with you instead of your passport. (you will need your passport if you leave the EU. You will need it for places like Slovakia, Poland, the Czech Repubilc, Ireland or the UK)
Have fun!