Hi Rusty dude
the best and cheapest way to do what you want is:
1) FAA PPL, Instrument Rating and time building.
(U can do this in 3 to 4 months)
2) Then JAA ATPL exams thru Bristol (residential in the UK or distance learning from afar)
You can do this bit in 6-7 months (If I can, you can!)
3) Then the JAA CPL and Multi Engine (about 4-6 wks)
All of the above u can do in the USA and save tons.
4) You will then need to do a UK CAA Instrument Rating back home (or elsewhere in Europe i believe) (between 3-6 wks)
The IR is one of the more important ratings you will do.
Here you will qualify to fly in IFR conditions, learning to fly without external visual references and with radio nav aids.
Best do this before the time building so that u dont spend your time on your arse waiting for the weather to clear up at all sorts of backwater airfields.
The FAA PPL will include a little night flying, and u dont need an extra rating to fly at night with an FAA PPL.
If you do all of this you wont need to convert to a JAA licence after your PPL (unless of course u want to fly in Europe before u have the JAA CPL.)
Regarding the JAA approved US schools - some I would avoid like the plague.
I have attended two and I strongly recommend EFT (european flt training)
They are fair, quite well organized, reasonably priced, and a good and above level of instruction.
Whatever route you choose - good luck mate!