what to do?

We've just put a little gym in our house, and I'm loving it! The only thing is, I'm bit unsure of what to do down there :0/ could anyone guide me? I've got a cross trainer (or whatever they call it here!) a stationary bike, a rowing machine, a stepper, and a multi gym. I've been going 4-5 times a week and my current programme (ha ha, that makes it sound very impressive!) is between 7-10 minutes on the xtrainer to warm up, then about 20 minutes of weights (I do 3 sets of 10 reps) - focusing on my legs, my arms and my belly (ugh, 3 kids..) and then I do about 20 mins of cardio afterwards. I think I need to up the cardio but frankly by the end I think I might die anyway - I'm not a natural when it comes to exercise!

Having not used the gym in about 8 years, I could really do with some guidance from people who actually know what they're doing. My DH is a sports physio and has shown me how to use the equipment safely but he's no personal trainer if you get my drift. Thanks in advance people x