For the sore fingers, I would also suggest a person play consistantly/frequently, even if it is ten minutes every day or so. This "playing" can be looking at various chord configurations and placing his/her fingers into those chord positions (use chords from several songs you would like to learn). This will allow your fingers to begin building up tough skin on the tips, eventually prolonging your ability to practice/play (it pays off!). This simple effort will also begin to develop the muscle memory and dexterity within a person's fretboard hand (it feels goofy at first, so be it) as well as teaches a person the relation between and the chord shapes and the sounds which they produce, so give the guitar a couple strums once the fingers are in the correct place.
If the chord you are trying to play is too difficult, play an easier version or a different chord altogether. With experience, as your other respondent mentioned, you will begin to understand how certain finger positionings will allow you to flow out of one chord and into the next chord. Eventually, everyone has his or her own style. Just put the time in and be willing to "fail" to succeed.
Last suggestion...take every opportunity to sit down with other players and learn through observation and question. People like to share their knowledge. Enjoy the ride...you'll suprise yourself!
Pura Vida mi amigo!