Photoshop Elements - I use version 6 as it's free from the internet. In the 'Editor' I used 'Enhance' - Adjust Lighting' - 'Shadows & Highlights' and slightly decreased the highlights and darkened the shadows, then added a tiny bit of contrast.
I could have done the same in Photoscape or Faststone, both of which are free downloads and very versatile editors. I use Faststone mostly as it is so intuitive to use and great for quick adjustments.
I have got a full version of Adobe Photoshop but never use it, firstly because it is so huge on my hard drive and secondly it is so comprehensive and full of clever stuff that I don't need. A lot of the applications are for manipulation and effects, and all I want is simple adjustments to get levels and colour correction.
That's a nice picture, I spend a lot of time shooting woodland details like that.