|Keep It Simple, Stupid|
First up, you have my heartfelt applause and admiration for keeping going and taking the part time route. You'll get a lot of support from the OU themselves, and other OU students (and its amazing how many you'll meet in everyday life).
Secondly, you also deserve applause for being willing to take a mcjob in extremis to pay the bills.
As to your question, I would not advocate commercial certification as a route into the industry for private individuals, especially not the more 'advanced' (i.e. expensive) certifications. Most of the commercial certification schemes (CNE, MCSE, A+ etc) are priced for companies. IMO you simply will not see the benefit of paying anything up to 10k for a certification which, without experience, is of dubious merit. Most of the boot camp companies pumping out high pressure advertising, suggesting a high paying career in the computer industry after a couple of weeks training at considerable expense, are IMHO carpet baggers after your money. I used to recruit a lot of technical staff for my last employer, and what I was interested in (sorry!) was experience, pure and simple.
A previous employer put me through several of these things (CNE, MCSE, CCNA, PSE) purely because they got large discounts from the manufacturers for having certified staff. Once I'd left their employ (paying back quite a large amount in training fees) the certifications did me no good whatsoever.
ECDL, incidentally, can be done at minimal cost, at your local HE college. No requirement to pay large sums of money to carpet baggers at all.
For my part, I got into the industry after leaving school at 16 by working in a dull, dead end job in a small insurance company, who suddenly found a requirement for someone who could write code (however badly) on the cheap. I've met a lot of people who got in the same kind of way. IMO you're more likely to get worthwhile IT work based on word of mouth, being in the right place at the right time, and/or being involved in the open source community than putting yourself in swingeing debt for years to come. If you're sufficiently interested in programming to be hanging around here, you'll find something eventually.
Oh, and make sure your CV says you're an OU student. Especially in this industry, you'll find that a bigger recommendation than anything else.