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.
Even if they use latin script, the name of the country is not always written the same in it's own language vs in English.