I have stayed at
Hostal Lopez and
Hostal Chelo . I will be staying once again at Hostal Chelo in February. I prefer Hostals over hotels in Madrid because they are more personal and a great value. Expensive hotel rooms are best at resorts like Sea Island when you will actually be spending some time in the room.
Hostal Chelo is basic, my bed was comfortable, there was hot water, heat and it has an elevator. They are very accommodating and a single costs somewhere around 30€. The Gran Vía metro stop is about a block away and there is a wonderful bakery between the Hostal Chelo and the metro.
Hostal Lopez is close to the Prado Museum/Retiro Park and costs a bit more. It does not have an elevator and we had problems with our keys opening the front entry door. The Antón Martín metro stop is 4 or 5 blocks away.
Hostal Adriano looks interesting, but I will continue to stay with Antonio and his family as long as they have a room. Hostal Adriano is on my reserve list should Hostal Chelo be unavailable someday.
You do not need experience to use the Hostals. I did it on my first trip to Spain and I was traveling with two kids. None of us spoke much Spanish. It was a great part of our adventure!!
Hope you have a wonderful trip!!