IF you can't shake loose the money to get the card paid off (or BT it to a 0%) then a mortgage's interest is at least tax deductible - look for one without a pre-payment penalty so you can pay it off at any time. Double check with a tax attorney/CPA - there are some restrictions on tax deducting mortgage interest which you may fall into, so check before you get one and then can't deduct any interest.
My mortgage is the ONLY bank I don't feel too bad about paying interest to - otherwise I think of it as wasted money. I hate paying interest on car loans but DH can get really good rates since he's in the business (and also great deals on cars) - and I can keep the cash liquid.