This is one of the most unanswered questions about the iPhone. And no, emailing is not an efficient method. There are apps out there that claim they can transfer from PC to iPhone, but research shows that these are problematic too. Apparently, the arrogance of Apple is such that it disallows effective PC to iPhone transfers just because it "looks" like a Windows function. Idiocy.
Anyway, the answer to your question is: No. And be wary if anyone writes and tells you to use Windows Explorer, or EasyShare, or whatever. I've tried; not good.