Guapetona, how right you are!
Ok, for those of you working on it:
If a parent or both parents were BORN in spain, and are spanish of origin, you can get nationality without the year residency. It does NOT matter if one or both of your parents acquired American nationality or not.
About renouncing. Well... that's another matter entirely. Technically, you have to, but it doesn't mean anything, only to the spaniards. If you were born in the US, one way or another, you'll ALWAYS be an american. This is a long topic, I've simplified it, but keep in mind that both nationalities are your BIRTH right.
Grandparent route... well, the person whose grandparent was born in Brazil, I'd have to know a bit more, but either way, the other grandparent was born in Spain so that qualifies you. Unfortunately, yes, you do have to do the year of residency, student visa does not qualify. The only 'special' kind of visa that I can think of that they may be talking about is that SUPPOSEDLY, if you have a grandparent that was spanish, then you're exempt from the condition of national employment in spain and the ministerio de trabajo HAS to grant you a work visa if you get a company to go that far with you. However, this doesn't really work.
Consualtes/Embassy and misinformation: Each one will give you a slightly different story. Make sure you research as much as you can and know what you're talking about and insist! You HAVE to be persistant, at the point of being a pain in the a$$!!!!!!!!!!!!!! Don't rely on what a person TELLS you, get it IN WRITING! Any correspondence you send the consulate they legally have one month to answer you back, or you can file a complaint and the trouble is more than its worth to them, so they'll answer. After getting the run around more than one time, I wrote and funny, all of a sudden, I got cooperation! The pen IS mightier than the sword! (And me, ready to handcuff myself to the consulate door!)
Guapetona, about your parents registering you... yes, this is one reason it was easier, but it SHOULD still be the same for the rest of us... I had a hard time getting them to register me, but finally it was done. As for the rest, the consulate I have to deal with is taking its time and I have to sit and wait.
For those of you with the America vs Spain. I can't speak for the rest of us half and halves... but this is me: I am very proud to be half American and Spanish. However, I identify more with the Spanish culture and yes, would very much like to go home. Many times its felt like being in exile because although it was there, because of misinformation and noncooperative people, I did not have the choice as to where I would be... Having been brought up on both sides, well, I think its difficult for any half and half to be COMPLETELY fine in one place. In spain there are things I miss about the US, but not as much as I do about Spain when I'm in the US- most of which has to do with family... But like I said, those of us who were born in the middle, well its difficult, siblings from that same mix will have different feelings and even pull towards opposite sides (one being 'american' and the other 'spanish') its not easy, just something we have to live with and do the best we can to hopefully make the best out of what it is we get from both cultures and build more bridges over those gaps between sides. Although I am eager to return home, both Spain and the USA will always be my countries- for good AND bad.
So please let's not make this into a political debate- that's a whole other thread. Let's also keep in mind that written words doesn't always convey in the best way the feelings or intentions of the author- and that many of us shorten some of our e-mails because of time constraints or being slow typers. I'm just asking that we give the benefit of the doubt and ask before we read into things and start getting all fired up over potentially something very simple.
I hope this helped clear things up!