I originally installed Drupal 4.3 on a RH Linux 9 and whatever PHP and MySQL version came with that. It has worked so well and been so stable that I saw no need to upgrade. However, 4.3 is getting a little long in the tooth and it is time to bite the bullet but I, obviously, have several issues for this upgrade.

Due to the PHP version, I am unable to upgrade in place and have decided to do a parallel upgrade, involving new hardware and possibly a switch to Windows as well.

Any rough idea on where in the heck to start?