SZF,
Residential, no question at all.
To answer your specific questions:
1) You're not allowed to start the CPL/IR until you've passed all the exams, so you don't have an option there.
A more common question is whether to hour-build before the exams. I think the best answer is no, leave the hour-building until after you've done the exams. That way, you'll be more current when you come to start your CPL. Having said that, there's nothing to stop you flying a little whilst studying - it'll keep you current, and reduce the amount of hour-building you have to do after the exams. Not to mention that it's fun - I couldn't imagine not flying whilst studying!
2) Definitely do residential. The only reason for doing distance learning is if you can't afford the time or money for residential. Having said that, you did mention getting a temp job. Are you running out of money? If you need to get a job, you might not have any choice...
3) Really not very much you can do here, the syllabus is completely different from PPL. About the only subject which I've fond to be similar was R/T, but that's so simple it's not worth stressing about until you need to.
Hope that helps. Good luck!
FFF
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