Pixlr is still my photo editing tool of choice for blog pics. It's online, it's free, and it has a decent tool kit which makes it accessible for scrooges like myself. The main purpose of my editing is not an aesthetic one, nor one that is immediately obvious.
I make pictures smaller.
Why? Because file size is something you need to be mindful of. Nothing makes me flee a post faster than having a whole set of high res pictures slowly loading on one page. If you want to make a gallery post, have small resolution thumbnails on the "landing" page which when clicked link to the larger image. It's more work but I guarantee your readers will appreciate it.
I make pictures smaller.
Why? Because file size is something you need to be mindful of. Nothing makes me flee a post faster than having a whole set of high res pictures slowly loading on one page. If you want to make a gallery post, have small resolution thumbnails on the "landing" page which when clicked link to the larger image. It's more work but I guarantee your readers will appreciate it.