I'd go for a 800 speed film, such as the Fuji 800Z. its a great film, with great colors, nice grain(not invisible by any means), but depending on what you're looking for, you might be in for a bit of experimentation.

I'm personally a Kodak fan though, the 160vc/400vc/ portra 800 films are what I run through my cameras. so, pick up a few rolls of each, and test them out. Some of the Kodak gold(200 pushed to 400) are quite nice, IMO. I went through a full semester of school shooting nothing but the Gold 200, and no one, even the teacher asked what I was shooting on, just commented that they really liked it.

its also cheap(well at least here in the US, not sure about in the UK)