Regarding the original post about making a clean start with GTD, my advice would be to take advantage of this situation by dong the following:
Quickly set up a good general reference filing system and stay on top of your filing.
Stay on top of your in-box processing. This is a great opportunity to keep them empty and your system really current.
Make sure you keep or start a good habit of regular (weekly or daily) reviews.
Doing these things will keep you on top of everything and prevent having to do any catching-up, which is always less efficient.