You may or may not be too old for the grad schemes. I went for interviews at 27 and although it techically doesn't matter, I did feel disadvantaged. It was harder to justify why I was now wanting to do consulting, compared to grads agaed 22 just finishing their managements and economics degrees. However, this is irrelevant. The fact that you have a 2.2 means that your application will automatically be rejected, unless you have some pretty water-tight excuse and you were on track for a 2.1 or 1st otherwise. The website applications often exlcude 2.2s automatically, without a human being even looking at the form.