I use a Boardman Hybrid Pro for commuting. It's very almost as light as the drop bar equivalent and I love it to bits.....HOWEVER, if I wasn't commuting then I'd have got the drop bar and it would have been a no brainer! The hybrid is just the perfect choice for all the stuff I have to carry if I don't want to have a rucksack (which I don't).
If you shop around you can probably kit yourself out for £200 but you will be value end. Might be the place to start and upgrade to better stuff as and when you can afford it. I've done precisely that after an absense of about the same time as you.
Thanks, it seems like a drop bar bike may be for me but I'll also bear in mind what has been said about bar types, gears etc and make sure it feels right on a long ride.
Regarding the winter, is it realistic to use something like an Allez 24 through the winter? I guess we're talking about going out for rides in conditions like light rain and occasional greasy roads, would I need to fit some different tyres, as I'm assuming the slicks would be a no-no?