What is the ideal amount of exercise one should do per day (in terms of cardio and weight training) for fat loss?

I'm no physical trainer, but I would suggest exercising in one way or another 5-6 days a week for at least 30 minutes at a time. Lift weights every other day, or if you want to do them every day, alternate between arms and legs. Muscles need at least 48 hours to recover after heavy weight lifting. For cardio, take up something you enjoy doing - rather it be walking/hiking, jogging, dancing, sports, swimming, biking, etc...and do that for 20-30 minutes as you begin and then increase when you feel stronger. You have to do what your body tells you, based on your personal strength and ability. Make sure you take 1 day of rest a week to recover.

Depends on the intensity...45 minutes to a hour during a three day split with lifting. 30 minutes of cardio on the offdays with at least couple of days with no exercise.