When I started, I saw there were two choices, paint shop pro or photoshop.
The two packages will do basically the same thing but I find photoshop will update the entire photo being processed opposed to a small preview in paint shop pro.
The Abode (photoshop) site offers a 'try before you buy' option which is well worth doing before parting with any cash - I think it works for a month which is plenty of time to decide.
Best of luck
Stephen Fox