iBook won't recognize usb ports

Hi all,
Any help here would be much appreciated!
My ibook (14" G4, 1.33Ghz) suddenly will not recognize my mouse or printer...both connected via the usb ports. I've tried swiching the mouse back & forth and it doesn't seem to want to see it in either usb port. I've rebooted and it recognized the mouse on reboot, but not the printer. So I switched the printer to that port...no luck - still wouldn't respond. Then I put the mouse back in that port and now it won't see the mouse again.
No idea what to do here, any help would be great.
Thanks

Have you checked whether the printer is compatible with your Mac? You may have to download and install the necessary drivers.

Everything is compatible...I've been using the same mouse and printer for the past year. The printer driver is up to date. I used the printer on Friday and everything was fine. And the mouse worked earlier this morning.