Ryanair to Ciudad Real ?
To get from Barajas to central Madrid on the metro costs 2.75 euros with a very frequent service.
To get from Ciudad Real station to Madrid (ignoring the metro):
Slow train (only 2 of these per day) takes about 3 hours and costs 17.1 euros one way
Fast trains cost either 19.2 or 34.7 euros if bought at the station depending on the train you take, go approx every hour and take an hour. Tickets for about half these trains can be bought in advance on the web for around 20 euros one way (about 16 pounds). For a very small number of trains, you can buy a ticket in advance for 13 euros - but be prepared to wait a few hours between your plane arriving and the train departing
Yes, in both Oslo and Stockholm, Ryanair flies to the middle-of-nowhere - but neither Gardemoen nor Arlanda are on the metro and trains to the city centre are expensive, meaning transport costs from Torp or Skavsta are competitive.
Given the time and cost involved, if flying to Madrid I'd need a pretty good reason - or very cheap airfare - to choose Ciudad Real airport over Madrid Barajas.