London Neighborhoods for expats - crime, etc.?

Hello,

I'll be relocating to London for a while in a couple of months, and I haven't been there in years. I have a job in Canary Wharf.

I'll be searching for an apartment in the first two weeks I'll be there - but until those two weeks all my searching is online.

I'm having trouble figuring out which neighborhoods / streets are safe at night -- which is not a concern in 90% of Manhattan (you can pretty much walk from anywhere to anywhere very late, alone) where I am now. With that in mind, what neighborhoods would you recommend I focus on, and which completely avoid, so I can feel relatively safe walking at night, and still not be too far from civilization? Some have been mentioned are: Notting Hill, St. John's Wood, Limehouse and Angel. However, no one seems to agree on what's safe and interesting, and what isn't. In particular, I expect to come home late a few nights a week, and be within walking distance of some places open late.

Thanks!