Recs for Barcelona

Hello,

My about-to-be-wife and I are spending three weeks in Spain, starting off in Barcelona, then going down to Seville, Grenada and thereabouts.

We've rented an apartment in Barcelona right next to the Santa Maria Del Mar church, and I just thought I'd see if anyone has any good recommendations close to there. Food stalls, holes in the wall, bars, mid-range, upscale, we'll try anything. Atmosphere is of course a big plus.

Thanks!