Following on from the above.. (as per everyone else)...
- Get a class 1 medical before you do anything else.
Then do 2-5 hours at a local school - ensure that you enjoy it! (Some people think they're mad keen, get in the plane, and don't like it! honest!). Get as many exams done as possible or start revising as soon as possible.
Then head to the states and do the PPL course - you'll need at least 4 weeks to complete it allowing for weather (not so much vis/cloud/rain - but wind - crosswind limits can ground you for days). If you're doing any flying before you go be aware that some schools will "get you to 45 hours" and having previous hours in your logbook may affect how much tuition you actually get. Be wary of that one if you've got 20 hours - if you've got five, just take a new empty logbook and start on page 2 and enter the previous later.
If you're serious considering commercial over a tight timescale, get your medical first before you spend any money!
Then be aware that you have to pass both the CPL & IR within 18 months of completing your last ATPL exam.