No reason to be embarrased. That's what the forum is for: sharing information.
Samurai Vampire = Sampire
Wraith Samurai = Wammy (Whammy)
They each use a different Necro spell characteristic for the added bonuses of leaching, healing, etc. I remember reading about them for the last several months and I'm certain that further - perhaps a lot further - back in the forum there are articles that discuss the exact characteristics, methods, +/- affects, etc of both. Seems that some persons are typically sold on one version or the other wholeheartedly so several camps have developed. Personally I use neither and don't intend to.
If I'm not mistaken the thumbnailed thread "For those who are unsure" has some content about them inside and there are more over about two or three pages back.
Probably not the complete answer you where looking for but hope it's at least it's a start.