Streetlife

I had my 30th at The Yorkshire Grey and it was great. Not quite Islington, but very close. I had sole hire as it's closed to the public at the weekend. You have the choice of the upstairs or downstairs bar depending on number of people. They have an iPod dock or you can bring your own DJ. I think the min. spend was about 600 quid for the big bar downstairs, which was easily met.
http://www.theyorkshiregrey.com/
Thinking of other places my buddies had 30ths - Canal 125 on Cally Rd has an upstairs room that you can hire too. Simmons was awful, they were very rude to by my friend / the birthday girl despite it being sole hire. We never went back.
There's more, but they're not coming to me at the moment. I'll have a think.

The Driver def. has a late licence and rooms for private hire, but I don't know if you can bring your own DJ or the cost of it.

Yorkshire Grey looks lovely! and £600 is a reasonable minimum spend. I'll contact them ty.
I'll check out the driver too :)

the hemingford arms has characterful room upstaires. In the summer I let out my garden with gazebo, and sitting room, for lunch or breakfast parties, with Gazebo, but cant have DJ unfortunately.

The Hemmy is a great pub too. I miss the days when "The Ivy" pub was my local.

I didn't know the Hemmingford had a private room!!
Thanks ladies :)

Try st Luke, recently refurbish and looks great.

The island Queen in Noel Road has an upstairs room I do know.
Very popular with the age group you mention.

Paul

The Chapel round the back of Islington market - you can hire either upstairs or downstairs

The Florence in Florence Street off Upper Street and The Cloudesley in Offord Road are offering their rooms for free!,

Thanks for all the suggestions!
Will have to organise a pub crawl to check them all out :)