Well, you mentioned the Nikon brand, they or Canon are a good choice.
Canon has the EOS line that you can grow with as far as lenses go should you decide to take an extreme interest in later on.
All can be used on full auto and are easy to use and then be able to get creative as your learning skills sharpen.
I do suggest that whatever you choose, spend time reading good books if you want to do more than point and shoot.
Nikon doesn't use as much hype to name their cameras but also has a progession of cameras and lenses one can grow with.Canon has the EOS line that you can grow with as far as lenses go should you decide to take an extreme interest in later on.
Sony has only been in the DSLR business since 2006 when they bought out Konica Minolta's photography and film business.And yet again us poor Sony users get left in the dust LOL. .
A used Nikon D90. I see them all the time for around $500-550.