Ncusack, you really need to get yourself a copy of LASORS! It's all on-line, but especially if you're looking at some of the more "exotic" options like converting foreign licenses or building hours on SLMGs or microlights, I would think the £10 for a hard copy which will give you definitive answers to these questions would be money well spent.
The requirements for CPL are that you must have 200 hours before you can start the course, and 250 hours before you can apply for the license. The basic course itself is a minimum of 25 hours, although this gets a bit longer if you do it on a multi-engine aircraft and if you don't have a night qualification before you start. So no, it's not just a case of hour-building and passing a test, you have to follow an approved course.
As to which aircraft, it must be what the Americans would call a "complex", i.e. retractible gear and constant speed prop. Piper Arrow seems to be the most common single-engined type, or just about any light twin that's suitable for training, but you'll use whatever aircraft your school has.
Hope that answers some of the questions.
FFF
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