Good hotels? Lots of choices. Reasonably priced, LOL...

The Westin is cool. It's The big glass cylinder that you see in pictures of Atlanta. The rooms are small but the outer walls are all glass. Get a room as high up as you can for really impressive views.

The Omni at CNN Center is very convenient to Centennial park and has all the CNN and Cartoon Network stuff to see and do.

I suggest biting the bullet and getting a good hotel as close to the park as you can afford, the convenience is worth it.

Things to do? The biggies are World of Coke, the Georgia Aquarium and the Civil Rights Museum. The SkyView Ferris wheel is fun one time...

Eat at the Varsity. Lots of interesting food and drink around, but the Varsity is classic. Go wander around Piedmont park for an hour.

Locals and Google will probably be more help, but these are the touristy things I like to do in Atlanta...

There is a Doubletree on LaVista Rd ( I believe off of 285) about a 20 minute drive to downtown... I have booked there in the past for around $ 110.00 / night

The Westin Peachtree Plaza Hotel opened as the world's tallest hotel. No clue where it rates now, but it's.... tall. A lot of the stunts from Burt Reynolds' Sharky's Machine were filmed there. The external elevator ride is cool, if you're not afraid of heights. They now charge admission for the elevator if you're not staying there, b/c it became a tourist mini-attraction.

If you want to stay at Centennial Park, the Omni @ CNN Center and Embassy Suites (Hilton) are probably the two closest to the park. Both are also near the College Football Hall of Fame. And on the other side of Centennial Park there is a Marriott property called the AC Hotel near the Ferris wheel and Tabernacle music venue. And I think an independent hotel called The Glenn. Those are all probably closest hotels from the park, all less than 1/4 mile walk.

[Edited on 1/17/2018 by Zambi]