I am going to go onto college next year to study English and computer science, each at A level and computer games designing at BTEC.
I am choosing to do these courses because I like the coding side and the designing side I also really enjoy writing. (In fact I am doing so game scripts through the classifieds.
Any advice or comments on the route that i should take?

I think you're doing the right thing, taking courses that interest you. If you have any specific questions, you should look at this forum's FAQs (I moved your post to the Game Industry Job Advice forum).

thanks for the advice and for moving the thread

Design positions are much, much harder to find and land. Even if you enjoy design better, take programming instead. Program well designed games, get noticed, get a job as a designer. At worse you get paid a good amount programming and continue to make games on the side until you land the designer job. Same thing applies to writing.

It really comes down to doing what you enjoy. Luckily there are enough tutorials and free programs out there for you to start now.

Grab yourself a copy of Unity or UDK for free and play around with them.

http://www.unrealengine.com/udk/downloads/

http://unity3d.com/unity/download

http://www.3dbuzz.com/training

I did this at your age when I wanted to get into the industry and discovered art and design was definitely my field. I went to Uni got a degree in game art and design and worked my way up the ladder. If I could go back in time, I would take the same course but at a better university with links to development teams.

You can do some research and find courses that openly advertise their links with game developers.

For design universities in the UK, I'd recommend Newport or Bournemouth but you have to be very good at Art or Programming to stand out as a graduate. Even then, your first job would likely be a junior artist, programmer or qa tester, but you'd be in the industry and that's half the battle.

For programing I'd recommend Hull University. A lot of our recent graduates have come from that university

And finally, remember to never stop improving yourself by learning new skills, techniques or methods. It's very easy to fall back and relax once you get the job and feel as though you are set for life. This industry is constantly evolving and the dinosaurs that fail to adapt to change go extinct quickly.

Designing games doesn't have set qualifications. I would recommend taking programming as this can still lead to a design job as well.