Rick Steves is a good guidebook for some people.. and I think it may suit the OP very well.. . I think some people need to remember that when a person has not travelled much outside their country that basic is good.. I have been to Paris many, many times.. and I don't use a guide book .. but do rely on the internet now to confirm opening times, admission prices etc..
Some people do not realize almost every major site in Paris has its own website.. and in English. Best place to go for up to date info.. just make google your friend.

I also think the HOHOs may suit OP just fine too.. and the tour buses have FOUR routes .. the other bus company (BIg Bus formely les Cars Rouge) have only three. And the two day pass is a better deal then the one day pass.. but do NOT prepurchase as frankly the one bonus of the hoho tour buses is sitting in the open top.. in the fresh air.. seeing the neighborhoods as you go through them, so good weather matters. I get car sick too.. but not just short drives like that.. remember you can hop on and off when ever you like.

Your hotel will suggest a terribly overpriced tour .. you certainly do not need to take a tour within Paris.. although I too think a walking tour by someone like Paris Walks is a good idea, but bus tours in the city , blech.