The Disney hoteks are far out East of the city, good for the better beaches but a long way out for all the major sightseeing places.
The best area is around Placa Cataluna, generally the eixample barcelona area, which is the old city.
Now you can walk to some properties from there but it's the transport hub, the start and end of the HOHO, and easy connections to the Gothic area, la Rambala, the market, and traditional shops. Also the airport bus terminal and trains to the airport.
We have stayed in properties in the eixample barcelona area, a couple of hoteks, but the best has been Hotel Jazz centrally located rooftop pool, trip advisor shows high responses including as a 3 star people think it's under * and should be a 4star.
From there it is three short stops on the subway to Stagrada or the HOHO direct, it actually could be walked but in the sun not advisable.
Many cruiers on my cruises have stayed there often booking early to get breakfast included and a discount, I understand for some Mediterranean cruises it is sold out.
An alternative is Crystal Palace to the north of Placa Cataluna, slightly nearer to Sagrada only two subway stops.
DCL hotels are expensive and unless you want a beach holiday only they are in the wrong place.