Day Trips
Frankly, if you haven"t been to Vegas (and apparently have limited time) I wouldn"t bother with day trips to the Grand Canyon or Red Rock.
Not that they aren"t worth doing but they certainly won"t be THAT inviting at the end of December. It DOES get cold in Vegas (even snows).
Breakfast
Breakfast @ Dennys...In Vegas? Why, unless one is desperate. Not that once can"t get value but there are so many better options. Hash House A Go Go for one
Steakhouse
All of the options mentioned are decent although I hesitate to recommend EVER eating at the IP/Quad.
Shows
I"m not going to comment as these are an individual choice. Certainly try and hit up Tix4Tonight
New Year is probably THE expensive time to hit Vegas (other than the Superbowl) and places will be packed. Book shows early and make sure you have confirmed reservations for any restaurant.
Paulie"s absolutely right in everything he says
EXCEPT to remind you that it"s not just shows that are personal preference!
We went to the Grand Canyon in either December or Jan - can"t remember. It
was snow covered and absolutely beautiful - we wore a woolly hat, gloves and fleece and had a magical day ......
Same for Red Rock which we have seen both in the cold and the warm and it"s still pretty amazing if you want something different to that which the srtip offers.
Denny"s - one in every other street all accross America - nothing spesh except that for $30 two of you walk out completely stuffed and the one that likes sweet stuff can have pancakes or french toast and syrup whilst the one that likes savoury gets his full english America style.
"course - if you want a hash brown with a varied choice of accessories there are other eateries!
We went for a steak at IP in March on our wedding anniversary on a recommendation from a local - we were nervous but needn"t have been - it was brilliant - a proper "old vegas" experience though I stress - it must be the restaurant on the 5th floor "Embers"- not one of the cafe style ones dotted about the casino, many of which may be gone by the new build - don"t know. In March they were saying that Embers would survive the modifications because we will certainly consider going back there next time in a few months.
Also you should consider a buffet - Paulie will know the best ones probably but we did a champagne one downtown at one of the old casinos and enjoyed it very much. Have also done the Golden Nugget one which is pricier but good.
Depends how long you"re there for. If it"s a short trip & first time, fair enough to stick to the strip but it can get a bit much so if you can get away from it for a bit it"s a bonus IMHO hence my suggestions.
If you"re going with your better half and want to get away to play poker I can recommend the best (and worst) spas for pampering days out etc - let me know. There"s also amazing shopping but I haven"t managed to do that very much in recent years since I"ve been playing poker - Mrs Snapper & Mrs Percival are the experts there me thinks!