Adobe CC has all of the tools needed for starting out, with all sorts of features that are incredibly beneficial to an editor or filmmaker, although is a bit more advanced and will require lots of practice and time to feel comfortable in the workspace. One downside (or upside) is that instead of buying a program, you have to pay for the program yearly or monthly. The downside is that if you are an amateur starting out or you have little time to be doing active filmmaking, you'll be paying for something you aren't going to use much. The upside to this though is that they sometimes add new features and fix bugs, so you don't have to wait for a new Adobe program each year, which is incredibly helpful to many editors and filmmakers. Mac & PC.
https://creative.adobe.com
Final Cut Pro is a good editor, especially for starting out. It wouldn't make much sense to purchase an older version of the program, but instead get FCPX if you want to go that route. It has all of the basic features that you need to edit, grade, and mix a film, with plenty of effects and such. They've made it more consumer friendly in recent years, so if you're new to editing, this is what you should do. It's a cross between a professional editor and a less professional editor. Mac only.
http://www.apple.com/final-cut-pro/
I don't know that much about Sony Vegas... although sort of seems like PC equivalent of FCPX. PC.
http://www.sonycreativesoftware.com/vegassoftware
There's also Avid and other advanced programs, but those are often complicated and more geared towards professionals.
Some more consumer-geared programs include iMovie and Windows Movie Maker.
I recommend if you haven't gotten your hands on editing programs before, you use iMovie or Windows Movie Maker, or really the default program on your computer. If you're working on a Mac, you could move up to FCPX or Adobe CC. If you're using PC, I'd recommend moving up to Sony Vegas or Adobe CC.
I personally feel most comfortable with Adobe and FCP, but it's different for everybody.
BTW, Resolve is a grading program.