While I'd recommend spending a night there (more relaxing break, somewhere to spend some down time before going out again) hotel prices will be high for the next week or so.
Not likely on the kind of budget and wanting evening entertainment included. Better go back pack and stay in Chinese hotel.
Asiankit, Google wiki travel Macau and the Lonely Planet thorntree forums for up today's and budget info. Particularly the latter. Firstly, make a list of what you want to see. Do you know anything about Macau that you and your wife may want to visit, experience? Then that is your starting point. My suggestion is to write a vertical itemised list. Then your total budget, and priorities in order for sightseeing etc..
I do recommend seeing House of Dancing Waters, even if you have tickets up the back, because of the effects, these are better seeing as most of the show is acrobatic and tricks are higher up, one could describe.
For hotels, go via sites such as Booking.com ( my fave as I find it easy and flexible ) , Agoda. A day is really not enough unless you like to party all day all night. The good thing is that ferries to and from Macau - HK are 24 hr. I always look up my destination on Wikitravel or Lonely Planet before travelling. Anyway, I hope you find what you are looking for. No one can tell you exactly what you are looking for but there always will be suggestions, so use those as your start point, and let us know how it went!