USB 1.0 needs upgrade

What would I need to upgrade from a USB 1.0 to the faster USB 2.
I have a G3 that was upgraded to a G4.
Also, I have an external hard drive case that contains a Sata HHD.
On the rear of the case is a fire wire port, but the cable provided has Sata plug on one end that plugs into my computer.
Can I run fire wire to fire wire and skip the Sata iconnection?
Thanks for reading,
Yodi

Do you mean you have a G3 computer that now has a G4 CPU? You'll have to get a new computer (2004+) if you want USB 2.0 (either that or a USB card). If your external drive didn't come with a FireWire cable, then your only option is USB or get an IDE->SATA adapter and connect it internally (faster than USB 1.x)