Against five? No, I'd be running at around the 'e' in the words 'Hey you!' I'm fortunate in that I've never been jumped, so I've never had to defend myself. Strangely, I'd never bother crossing the street, because I tend to find people are pretty happy to meet a friendly, cheerful bugger who treats them enough like a human being to ask them if they're having a nice night.
Besides, if five people want me that badly, crossing the street isn't going to make much difference.
If it came down to a one-on-one situation, I really couldn't say who'd come out on top. I have no real experience, but if I knew it wasn't going to end up going too far (i.e. the guy wanted me dead) and I knew I couldn't get away, I'd at least give it a go. Granted, I'd fight as dirty as possible, but that's because I know I'm no fighter.
As my pal put it (and I trust him completely on this); 'When it comes to a fight, the bigger b****** wins. If you're willing to go further than they are, you're in with more of a chance.'