Fitness for Mommies and Babies

My fitness level is at an all time low. Though I've lost most of the weight gained during my pregnancy, the tummy flabs i.e low hanging skin with some but relatively little fat, refused to shrink. I used to go to the gym and play tennis regularly before I had Jeremy but I guess now I'm just too lazy to start a rigorous fitness regime again. Someone recommended Fitness for 2 to me when I was pregnant, however I was advised against any form of pregnancy aerobics by my doctor although the classes were conducted by qualified pre and post natal instructors. I' m now contemplating whether to take this up again as they also offer low impact exercises involving both mother and child. The classes appear interesting and enjoyable plus you get to meet all the new mummies and enjoy tid-bits at their cafe. I'm particularly interested in the Mummy & Mover Fitball (for crawling babies) programme. Who knows I might just sign up for this once Jeremy starts crawling. Has anyone tried any of their fitness programmes?