It depends what you wan't and are looking for. Like others have said what are your interests?
Do you want to stay off the beaten bath (the strip) and stay somewhere within driving distance?
My mother who comes to visit often always loves going to Red Rock Resort. Her immediate family lives here and every time she and her brothers and sister get's the chance she goes to Red Rock. She's never actually stayed there but loves going there. She is in her 50's. The poker room there is great and they have a great floor staff with soft games going. Red Rock is off the beaten path and there are many areas that your mom can go see if she is trying to stay low key but still be in Vegas. There is angel park if she golfs and Downtown Summerlin is right next door if she want's to go shopping/people/watch etc. Also, if you do want to do something on the strip it's a stones throw away. Do yourself a favor though rent a car and come down on a Wednesday-Saturday thing. You'll save a lot of money and be able to do a lot more activities if you have your own vehicle.
Alamo
https://www.alamo.com/en/home.html
Red Rock Resort
https://www.redrockresort.com
If Red Rock doesn't look like your thing take your mother to Resorts World. It's the newest casino on the strip and within walking distance to Fashion Show Mall and the Wynn/Encore.
That was for Las Vegas. For the rest of North America well, that spans 3 countries. It's going to matter where she has been, whether she likes cold or hot weather, or if this is pure vacation with poker on the side. If thats the case I would even recommend doing a poker cruise. Poker, Drinks, Food, Exotic Locations, Recreational Activities? What's not to love?
I recommend CardPlayer Cruises
https://www.cardplayercruises.com
Just make sure you are up to date on your vaccinations
The benefit of doing the cruise is that many of their ports depart from cities that already have popular poker rooms i.e. Los Angeles, Miami. Cruises will take you down to Mexico from Los Angeles, the Caribbean from Miami.
I hope you guys a great vacation OP!