When taking gifts to American people, small gifts of Japanese origin are very much appreciated. Gifts such as chopsticks, Japanese traditional folding fans, Japanese Ukioe, Japanese lacquer ware or Japanese ceramics are always very much appreciated. Also, many people appreciate a Japanese newspaper or Japanese money as souvenirs. Don't give gifts as a bribe. It is best to give a gift after a favor is done, not before.
Money is usually the best type of gift.
Wedding anniversary gift. Champagne is always appropriate. DO NOT give money. Flowers with a card are sufficient. Again champagne is good.