Nope -- break it up into major muscle groups, each once per week to allow recovery. Here's a sample:
Mon: chest & tris
Tues: back & bis
Wed: legs
Thurs: off (or cardio)
Fri: shoulders
Sat: off (or cardio)
Sun: off (or cardio)
A thing to note about lifting - personally I think that good form & intensity are more important than going for the heavy weight. But by the same token, as new@ says, don't screw around w/ the little pink 3 lb weights. You'd be amazed at what the body can do when you challenge it! She doesn't have to worry about "getting big" because she just can't, unless she's doing several years of heavy training and / or as. So don't worry about it. Get her to lift hard and go after it with a vengeance if she's looking for some serious results. Resistance training is key to losing body fat! Well, that is, second to diet of course!
Cardio is optimally done in the early morning on an empty stomach or else immediately after a workout. If she's just getting started, she may need to work up, so start at 30 min, get it up to 45-60 min. I generally try to do 4-5 days of cardio / week - pick the days or schedule that is most efficient for her schedule. Check out WarLobo's thread "When 30 + 30 NOT = 60". Good info on doing cardio!
And finally - get in those rest days to recover. A note about getting started with training - the first couple days on the new schedule, she'll probably be sore. That isn't an excuse to not go to the gym on the next scheduled day. As a matter of fact, getting in there and warming up with maybe 10 min of low pace cardio will help loosen up the tight muscles. If I dont' get in there and keep moving, I just stay sore & stiff for up to 4 days after. That sucks even worse.
Good luck! Maybe even get your girl on the ladies board so she can ask questions! There's lots to absorb for a newbie - not the least of which is the importance of diet, 6 meals per day, enough protein, good fats, etc. The media has polluted the public's understanding of nutrition so badly, its no wonder that more than 50% of the US population is overweight -- even with all this so-called non-fat, lite and "healthy" food.