Cinman,
I can recommend a book by Clive Hughes - I can't remember the title, but it's something like "Becoming a pilot". This will answer all your questions about getting an ATPL(f). There is also a publication called LASORS available from the CAA, which is supposed to be excellent, although I haven't got my hands on a copy yet.
To answer your questions:
If I take my IMC, does this contribute any hours/effort towards the full Intrument Rating?
No. It used to under CAA rules, but it doesn't any more under JAA rules - this change of rules is a possible source of confusion. However, although it doesn't actually count for anything, I'd imagine that having an IMC rating and some time in IMC would make the IR (which is, apparently, one of the hardest ratings you'll ever do) much easier.
And does the full-blown IR count towards my CPL/IR?
The IR is an essential part of the CPL/IR. The CPL/IR (aka ATPL(f) in the UK) basically consists of a PPL, ATPL exams, CPL and IR - usually in that order, although you can do the IR before the CPL.
Finally, I understand some Flight Simulator time may contribute towards my PPL(A)
Not true. Flight sim time on approved simulators can count towards an IR, and I think towards an IMC too but I'm not certain. But not a PPL.
FFF
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