Beginers really should start with a full body workout. Do it for at least a couple of months, or until you find that the time taken to get a good fullbody workout is taking too long, the split the groups up. I'd suggest that you work with free weights rather than machines as they also work the stabilizer muscles, not just the targeted area. Start with the larger muscle groups as they use the most energy. They are... legs, back, chest, shoulders..in that order. But it may pay you to seperate legs and back a bit, because they can use the same muscles as stabilizers. Dont worry about too much about the smaller muscle groups yet(arms, abs) as they get worked doing the larger compound movements. Start with one or two sets for each group after a warmup of that area, and aim for about 8-12 repititions. Make sure that the weight you use is what makes you honestly struggle for the last 1-2 reps, they are the ones that actually do the work. You can find good exercises and tips here
www.exrx.net