Well I would first suggest sticking to machines for now as opposed to free weights. Also, start off with light weights so that you can get your form down on each exercise. Once you feel like your form is good and you are able to do heavier weight then consider going to free weights. Push ups are good when you are starting out and stretching before and after your workouts are a must. I would suggest doing circuit training for your whole body when first starting out. Circuit training is when you do about two sets for a certain body part and workout your whole body in one day. But its up to you, thats just my preference.
Hope this helps and keep on lifting........................peace