I stayed at the Treasure Island hotel on the Vegas Strip. It has a pirate show in this lagoon in front of the hotel that's pretty spectacular. Canons, mermaids, sword fights, the whole deal. The rooms are nice and not super expensive, and the spa is very well equipped. It's not the fanciest place on the strip, but worth it if you're not a high-roller. I loved the decorations of the Paris hotel, and the staff even addresses you in basic French! The Bellagio is obviously a very posh place. If I go back and have some cash to spend, I'll either stay there or at the Luxor (it's shaped like a Pyramid).
You can get a lot of entertainment for free in Vegas because the hotels always have something going on. The Excelsior has a jousting match, the fountain show at the Bellagio, the art gallery at the Venetian, etc. You'll find lots of fun stuff to do for sure!