ok, theres a few things you'll need to consider.
1. Money
although you can qualify for a loan from your Local Education Authority , in some situations (ie, mine), it can be not enough to actually live on each year. Having about 5k savings in the bank would help if you dont want to have to work during term time etc. Working in the summer is a necessity almost just to pay off and/or prepare for those term time bills.
2.Getting in
Your a mature student, which for the most part means entry requirements mean **** all.
click greater london here
press go, and choose a subject
that should find you the uni's you are looking for.
Now, what you -may- find , is that you do not have to use the UCAS admission system. The best thing to do is contact the university in questions admissions dept, whom will be able to advise y ou on what exactly you need to do.
Also, email/phone some course leaders (again, this should be on the website) and you can discuss courses etc, or you can attend an Open Day at the university, again of which you should find info on the web.
3. Career Prospects
Right now, there are less jobs in computing than there are graduates each year by quite a bit. This might or might not pick up in the 3-4-5 years you could be in uni, so i would say that something more telecoms based would be a better decision, although the choice is yours.
I think thats the basic things, if theres anything else, ask.