If you're using Windows I'd expect the deleted character folder to be moved to the recycle bin, but whether that folder contains info marking it as dead is unknown to me. Also note that resurrection requires you to get rid of the ancestors file (or whatever it's called), as its log of the character's death prevents the usage of that character name for a new character.
If the character folder is in the recycle bin, I'd expect it not to show up in a disk search for removed files/folders, as the folder still exists (unless the bin has been emptied).
Personally I try to copy the character folder after every play session, removing the set once there's a hundred or so of them (keeping the latest, of course). While UrW is very stable, there is still the occasional fatal corruption (I think my latest case was caused by a power outage, something that's very hard to protect against in a program).
Obviously, though, it makes it very tempting to resurrect characters that died legitimately.