AB,
Since you're starting out again I would perform a full body routine for about 4-6 weeks to acclimate your body/muscles to the physical activity & soreness. Focus on compound movements (i.e. squats, deadlifts, bench press, pushups, dips, curls, etc.). Perform full body routine 3-4 days/week with rest days in between for muscle recovery.
After you get accustomed to the weight training and you can see/feel your muscles responding appropriately you can mix it up or "shock your body" so to speak. Change your routine to a more body part specific split. For example, do Chest/Triceps Monday; Back/Shoulders Wednesday; Biceps/Legs Friday. You can interchange your splits however you like. Everyone is different so figure out what works for YOUR body.
I would perform anywhere from 20-45 min of cardio as well 3 times a week. Mix up the duration & intensity to keep your body guessing. Obviously, if you're trying to pack on muscle it would probably be best to shorten the amount of cardio you perform but, again, figure out what works for your body.
Finally, Nutrition Nutrition Nutrition. Cannot emphasize that enough. Plenty of protein & good fats. In the gym is where you tear down your muscles. Outside is where you build them back up.
I don't post much except for the lil tidbits here and there so hopefully you find some good use of this. Remember this is a lifestyle change. I will also throw out the cliche you find here on a gambling forum...."its a marathon not a sprint"
GL in your transformation!
Stoner:cripwalk: (Just b/c this is my fav new smilie)