hi,
when you get the G5, don't install classic...
first install 9.2.2 on the G4 (normal upgrade to find at apple...)
and if you do as duff-man says ;-) target-mode... much faster than etherent... just copy all to you G5 and assign your just copied folder as the classicfolder... it should keep all your old programs in there and make them work on your G5 and you get all the rest too :-D
keep in mind that OSX uses a different assignment for the desktop files... so you'll find the old ones in a folder on the harddrive... but you can transfer them easily where you want them...
grts
Jo