Thanks for the further replies, bless you all for being so helpful, i really appreciate it 
BeattieBow - your situation sounds great, but you have hit the nail on the head when you say that it's financially positive for you to work. You deserve it, you have no doubt worked incredibly hard to get where you are, and no doubt continue to work hard, so hats off to you! However, i fear I am looking at a far more modest salary than you 
RockChick - i'm liking the idea of bank cashier actually, but would also seriously consider retail and call centre. To be honest, having had a good think about it all, I think i'll really just be lucky to get any job that fits my requirements and offers a non-insulting wage! For it to be really interesting and/or meaningful would be an added bonus!
I am 100% up for retraining etc, but i do worry that i'll invest time and money and energy in this, only to find myself pigeon-holed, or fit only for very specific work. Which is great if that work is around, but i feel that as i'm not the ideal employee, i have to accept that others may be getting jobs before I do. Depressing, but true.
I think the most feasible options right now are...
admin/temping
retail
GP/dentist receptionist or similar
Okay, none of them make me joyous with enthusiasm, but I could happily do them all. I do feel a bit sad that despite doing pretty well at school, getting a degree and working full time for nearly ten years, i'm basically looking for jobs that a school leaver might be looking at.
HOWEVER, if anything makes this worth it, it's having my DC, and who knows what opportunities lie ahead. Even if i have to tread water for a few years, maybe my horizons can be broader when the DC start secondary school.
We are very fortunate in that DH earns a salary that we can all live on, and i never forget that for a moment [touches wood]. But i don't want to be on the scrapheap just yet 