Good Luck with the cycling Moe. You'll find if you slowly build up what you do it gets easier and easier.
I find that the easiest way for me to get time and motivation to cycle is to combine it with shopping! I sit my 5 year old on the back of my bike and walk it to school and once I've dropped him off I do all the running around I need to do (banks etc) before going to the supermarket and filling up my paniers (with healthy food - honestly!).
I would love to be able to swim more (another exercise that doesn't overload my knees) and we do have a local swimming pool but my youngest son's school insists I'm contactable at all times as he has some learning difficulties.
Just by cycling I've lost 56 lbs in four years (only another 140 lbs to go! yes really 140 lbs

)