First time winter in Spain, help & advice

We are hoping to travel to Spain early next year. Intending to take the ferry to Santander then drive down to the South. There will be myself & my husband and our labrador dog. I having being looking at the sites on the CC list, but the more I read the less easy it is to decide which one/ones to book. I have ruled out any which require dogs to be muzzled, that leaves many to go at. Can anyone tell me are  sites such as Camping Cabopino very busy during January & February as this type of site certainly seems to have good facilities. Ideally we would like access to a heated swimming pool, Wi-Fi, showers/laundry. We like to walk a lot so nearby places of interest would be a bonus. I know it sounds like we want the impossible but I would really appreciate some ideas of where to stay from people who have done this trip previously. We are intending to stay about 8 weeks maybe at 2 different sites. Thanks G