Hello, Amy!
Great questions!
You can use Disney Vacation Club Membership to stay at many non-DVC resorts for a small transaction fee ($95 at the time of this writing.) The number of points per night varies depending on day of the week, time of year, resort and room type/view. Currently, a mid-week, standard view during Value Season at Disney's Caribbean Beach Resort is 17 points per night. A mid-week Value Season, Lagoon View at DIsney's Grand Floridian Resort & Spa is currently 55 points a night. Of course, check out Disney Vacation Club.com or call (800) 500-3990 for more information.
If using your points to stay at a DVC resort, you can also pay for additional days' worth of cleaning, too. Currently, Full Service is $30 per day in a studio, $45 per day in a 1 bedroom, $60 a day in a 2 bedroom and $75 a day in a Grand Villa. For Trash and Towel Service, these rates are $15 (studio), $20 (1 bdrm), $25 (2 bdrm) and $35 (GV.)
We've taken several cruises using our DVC Membership to cover the cost for all four of us, on both the Wonder and the Dream. Again, a $95 transaction fee applies to such a booking at this time. We'd never have been able to cruise so frequently on such beautiful ships without the use of our Disney Vacation Club Membership. With the benefit of banking points to the next Use Year as well as the option of borrowing points from the following Use Year, it's possible (theoretically) to use up to three Use Years' worth of points for one trip. Please note that this is a benefit that is available to Members who purchase directly from Disney.
Only you can know if this is right decision for your own family, of course. Please send me more questions about Disney Vacation Club Membership or any stay in Walt Disney World. I'd love to help!