Alright... here we go..

My current XBL acc. is on a CC (Credit Card). I have already did the necessary to make sure it doesn't renew because the CC is now expired.

1. Do I have to cancel my Gold Membership entirely via Xbox.com/Customer Support first?
2. Can I just redeem a Card that i've purchased to overlap the current Membership before it runs out?

Thanks to any that can help! I've tried over at the Xbox forums and I RARELY get responses. But here theres alot of helpful nice people... again thanks if you can!

1. No

2. Yes

You should also remove the expired card info.

If you aren't going to be using the credit card, I would definitely suggest calling Microsoft and having it removed from the account. Unless Microsoft added an option in the past few years, there is no way to manually remove a credit card from your account. A while back my XBL account was hacked, and a few hundred dollars were charged onto my mom's credit card. I called Microsoft and had the card removed and the account cancelled, but the damage had already been done.

http://support.xbox.com/en-US/billing-and-subscriptions/manage-payment-options/remove-xbox-live-payment-option

AFAIK, it's always been there. It would be silly to not include it, as you need to be able to update your credit card when it expires.

I guess they added this, finally.

Or maybe I'm just really dumb. But I do remember visiting the manage payment options back when this happened, and not being able to remove the credit card.