<<I will have one free ticket>>

25,000 Skymiles is sufficient for one Delta economy class ticket within the continental United States. An award flight to Europe would require 50,000 Skymiles. Note that these are the amounts required for "SkySaver" awards which are limited availability, a "SkyChoice" award doubles the mileage requirement.

It seems a good idea to apply for the Delta credit card now to liberate your old miles, but you should compare frequent flyer programs before deciding whether to accumulate Delta miles ongoing. Only then should you decide which credit card to use. If you choose Delta's own credit card the miles are automatically deposited in your Skymiles account which is convenient, but also limiting because Delta does not permit transfers to other programs. There are several other credit card programs that earn points which can be converted to Delta miles when you are ready to redeem a flight. This gives you the possibility of transferring to another airline if award availability is better, and protects you during Delta's bankruptcy.

In short, I wouldn't feel married to Delta just because I discovered a cache of miles. I would do whatever is necessary to use those, but I would separately evaluate whether Delta is the best for my travel plans.

dennis