I started out with Audacity but it only took me a month or so to get frustrated/annoyed with it. From recommendations on here, I started trialling Reaper and have been using it for precisely 25 days. I think it's great. I'll buy it because it's cheap, never crashes, easy to use, LOADS of functionality and capability to keep me going as I progress.
Heaps of people that know what they're doing use Reaper, so there is a plethora of specific user guides, forums, youtube videos, etc. to learn the stuff you need to on the fly. I don't know anything on the other software available, but if you're just starting out I don't see how anyone could be disappointed with Reaper. Ticks a lot of boxes as far as I'm concerned.