There are some very good and inexpensive soft ware choices, especially if you just want to do basic stuff.
Me, I use Picasa to view, discard images and make minor changes. This software is free, and it's basic editing features suit me, plus I really like the album and up load features.
If need to make any more specific tweeks then Paint Shop Pro is a very helpful editing tool, and at around US$79 it's a lot of software for a very reasonable price.
Photoshop and Light Room - Life is too short, I'd rather be getting the shot / trying to get the shot rather than providing artisitic additions after the fact