My personal favourite, and what I think about when people say 'real' vampires, are those of 'Vampire: The Masquerade', in White Wolf's 'Old World of Darkness'. Sunlight was fatal if they were exposed for more than a few seconds, their bodies were more resistant to mundane injuries but immune to nothing and they were dependent on blood not for survival but to stay animate and call upon most of their powers. They were also divided into several vampire families, called clans, that determined the powers they had the easiest access to and the type of curse they were put through; for example the Nosferatu were hideously ugly, so ugly that they could not be mistaken for humans under normal circumstances whilst the Venture had to limit themselves to a certain kind of mortal, job description, ethnicity, religious beliefs etc etc, to gain any kind of sustenance.
Mostly, however, I was enamoured to their ways of coping with their new natures. The transformation left them all with a monstrous destructive side, called the Beast, that would try to corrupt and destroy everything around them, regardless of what it meant to the vampire, or sometimes it would target those specifically because of that. They had ways of keeping the beast under control, mostly by maintaining their humanity, but things like violence murder or even simple theft made the Beast gain just a little more ground, and it was ground hard-won. Pardon my rambling, but these are what I consider proper vampires; not overly powerful though significantly more powerful than your average mortal, locked in a struggle with their own bestial nature and unable to rely on anyone but themselves and perhaps those few vampires nearest. And even those you'd be better off watching with care, too.
Mostly, however, I was enamoured to their ways of coping with their new natures. The transformation left them all with a monstrous destructive side, called the Beast, that would try to corrupt and destroy everything around them, regardless of what it meant to the vampire, or sometimes it would target those specifically because of that. They had ways of keeping the beast under control, mostly by maintaining their humanity, but things like violence murder or even simple theft made the Beast gain just a little more ground, and it was ground hard-won. Pardon my rambling, but these are what I consider proper vampires; not overly powerful though significantly more powerful than your average mortal, locked in a struggle with their own bestial nature and unable to rely on anyone but themselves and perhaps those few vampires nearest. And even those you'd be better off watching with care, too.