DPP will get you started, in fact, there are numerous POTN users who happily use DPP for working with Raw, and then they use an "image editor" for other things they want/need to do. For that type of thing you may want to look into Photoshop Elements, although since you've been shooting and working with jpegs for the past year, well, there's nothing "new" there unless you want to "step up" to a higher level of image processing.
Now, you've heard about Photoshop CSx and Lightroom, and in time you may want to "buy in" to more elaborate software. I'd just say "take your time" -- read up on software you may be interested in. When you feel like you are ready to delve into something, download the free trial when you have a month that you can devote toward the "learning curve". And realize, these complex programs do have a learning curve! For example, Lightroom has a ton of enthusiastic users here, but to get started using Lightroom effectively, you need a concept of Digital Asset Management (DAM) which Lightroom embraces from the "get-go", organizational tools at the core that myny folks getting started don't grasp and so get frustrated.
So, if you're considering Lightroom, I'd start with getting a good Lightroom "primer" (such as the book by Scott Kelby), downloading the free trial, and spend the month walking through the primer one page/tutorial at a time, and in the meantime you'll have DPP, you can get work done (although you can't "share" Raw processing between DPP and other apps). And then, if you do get comfortable with Lightroom or PS CSx or whatever, you still have DPP as a "reference". You'll not that your initial previews/renderings will look "different" with different Raw processors. DPP is nice because you can choose a PIcture Style to get a "jpeg look" and then you can look at the DPP settings and use them as a reference to "tweak" things in your other Raw processor!
And, welcome to the "Digital Darkroom"!
