For what it's worth, Spain's Royal Language Academy has called the language "español" since 1923, and 89% of Spaniards reported being fluent in it in 2005. So saying Spaniards don't speak Spanish is like saying Americans don't speak English.
There are five co-official languages recognized in the various regions of Spain: Castellano (everywhere), Aranese (Catalonia), Basque (Basque Country), Catalan (Catalonia), and Galician (Galicia).
In addition, there are several localized languages, that are not "official" but "recognized": Aragonese (Aragon), Asturian (Asturias), and Leonese (Castile and León).
For what is worth, Galician is essentially a variant of Portuguese, in the sense that it's mutually intelligible with European and Brazilian Portuguese. There are differences in pronunciation but not significantly more than between European and Brazilian Portuguese.