Q: Transfer data from Powermac G4 to new 27" iMac

I have a 2003 PowerMac G4 that I am replacing with a new 27" iMac 3.4 i7 which is on order. I want to transfer my photos and iTunes files to the new machine. I had purchased a LaCie d2 USB3/Thunderbolt harddrive in hopes of backing up the G4 but it is "not supported by this architecture". The G4 was updated to USB 2. The LaCie is USB3/USB2 compatible.

Can I use Migration Assisant going form a pre-Intel computer to an Intel based computer? Is there a Firewire 800 to Thunderbolt or USB 3 cable? There is about 200 GB that I need to transfer.

Any suggestions?

Hardware Overview:

  Model Name:          Power Mac G4

  Model Identifier:          PowerMac3,6

  Processor Name:          PowerPC G4  (3.3)

  Processor Speed:          1 GHz

  Number Of CPUs:          1

  L2 Cache (per CPU):          256 KB

  L3 Cache (per CPU):          1 MB

  Memory:          2 GB

  Bus Speed:          133 MHz

  Boot ROM Version:          4.5.7f1

  Serial Number (system):          XB31102SN1S

  Hardware UUID:          00000000-0000-1000-8000-000393CACB46

FireWire Bus:

  Maximum Speed:          Up to 800 Mb/sec

System Software Overview:

  System Version:          Mac OS X 10.5.8 (9L31a)

  Kernel Version:          Darwin 9.8.0

  Boot Volume:          Macintosh HD

  Boot Mode:          Normal