Best hotel in Las Vegas

My sister in law loves the Excalibur and Caesers palace, The Rio.
She is a casino freak!

The Bellagio, and certainly the Excalibur (I had a blast at the medeival dinner), and Caesar's (they used to have great magic shows deep underground, hear its changed) are also cerainly great places. They are all so much more than just hotels.

I stayed in the Bellagio when I went. It was my honeymoon and I got to stay in the big suite up at the top. It was so beautiful. The atmosphere was wonderful and I felt like I was in a victorian villa. If I was able to go again I would stay and the MGM Hotel. That hotel was more hip and party like. Bellagio worked for the honeymoon portion of the trip.

Harrah's is my favorite hotel in vegas. Location is great. Always treated well. Rates aren't too bad either.

Me and My Wife stayed in the Luxor and It was very Nice I thought and kinda near everything so that helped me out alot since I cannot walk to good But I also have a good friend who lives out there off the strip so next time we go we are going to stay with him an use his car to get around..lol
But he is my best friend so that helps.
But I loved the Luxor.

New York, New York. Treasure Island. Atlantis

I have friends who visit Las Vegas regularly and they had 3 choices as you asked here they are
One of the few hotels with no casino of its own, this elegant Las Vegas hotel is admired for service, good taste and attention to detail. The lack of a casino is a plus, providing a quiet retreat from the chaos just below; rooms have panoramic views of the Strip. The hotel is located on the upper floors of Mandalay Bay, and guests have full use of those facilities. The Four Seasons also has a private pool with complimentary cabanas. Nightly rates from $200.

Noted for its jaw-dropping décor and standout dining options from the likes of celebrity chefs Emeril Lagasse and Wolfgang Puck. On-site Canyon Ranch Spa wins kudos for its fitness center. Guest rooms are among the largest around, at 700 square feet. Nightly rates from $175.

Inside and out, this beautifully elegant resort with an Italian flavor even has a posh atmosphere poolside. Fabulous dining options and designer shopping complete the experience. Spring for room with a view of the dancing fountains. Nightly rates from $140.

any one of the three is great Good Luck

I have been to Vegas once a year over the past 15+ years. We have stayed on the strip every time. There are many resort hotels that have very comfortable rooms. However, I would love to stay at the Four Seasons at Mandalay Bay. I doubt that will ever happen, because I understand it is quite pricey. We may stay at the Mandalay Bay's hotel (not the Four Seasons, though) the next time we go. We stayed in a beautiful suite in Treasure Island several years ago. Probably 10 years ago, we stayed in a huge suite at Stardust. After that, the hotel went downhill. I think that most of the newer hotels (the last 10 years) on the strip have rooms that are quite comfortable.

There are new casino/hotel built in Vegas every year that we went down there, it's hard to tried them all.
I think the Venetian has some of the best rooms, even though it's on the hight end, but the smallest room they have is 550 sq ft.
Bellagio is much more costly for what they have, room is nice and if you want a fountain view, prepare to open your wallet.
Just stayed at the Planet Hollywood this last trip, was pleasantly surprised. We request the Fountain view room, price was actually reasonable, the room was themed and decorated with Planet of the Ape's pictures and movie costume. It was nice watching the fountain shows, have a relaxing drink at the privacy of your own room.