At the beginning you have to learn some chord.... get some easy ones THE MAJOR CHORD at first, then you'll learn some MINOR CHORD...
The important is to get the finger at the right position, make sure that is sound right when when you strum all the strings... Practice brain and finger muscle by switch from one chord to another one and getting the finger at the right place...
Then you have to learn some strumming pattern and get some rythm !!
With major and minor (and 7th) chord, you'll be amaze how many song you will play !!
Some books are good, but some are WAY too beginner, I suppose you don't want to learn, Mary as a little lamb !!
Books and DVD are'nt the best way, from my point of view. A DVD won't show you the mistake that you make, and bad habits are hard to correct later. A teacher or a friend could show you the way to do it right !!
Take it easy at the beginning... don't play for too long period of time, but play OFTEN.... short period...
COME BACK,... and tell us your progression, ask your question, we will help you out !!!!