Panasonic have been making some kick ass digicams recently, with ludicrously good features and optics for the prices. However, this comes somewhat at the expense of build quality.
A commonly reported problem with the FZ5 is the lens becoming stuck in one position. This is because the cogs that drive it are made of plastic and the mounting for the lens motor is a bit flimsy. A Panasonic service centre will charge quite a bit just to look at your camera, let alone fix it, yet this is a relatively simple thing to fix if you're not afraid of dismantling things.
Of course, you do this at your own risk, not mine. I can't offer any guarantee that this will work for you, but a few people have had the same error and performed the same fix successfully. Work carefully and it should be fine. This may also be applicable for similar panasonic compacts, such as the FZ7.
(Note on photography: I captured the LCD screen and balanced it with the rest of the scene by bouncing a powerful flash off a white blanket on the floor of a small room, which also had a white ceiling. At around 1/80 - 1/100 of a sec, the 16 feet or so the flash light had to travel balanced the screen and the rest of the camera up well, and provided good diffuse lighting for the innards of the camera).
Step 1: Tools
Tray (In this case just a flipped Shogi board)
I forgot to record the sizes, I just tried out tools from sets of screwdrivers and allen keys until I found the ones that fitted best. Even though the screws on the camera are posidrives, a flat head screwdriver was the best fit.
I also swapped the tweezers pictured for some round ended ones when it came to dealing with the ribbons because I didn't want to accidentally scratch or pierce anything.
Also very useful:
The torch was handy for peering at secluded fixings, and I used a piece of scotch tape to hold screws as I removed them.
The tray was absolutely vital. If you disassemble stuff without a tray, small screws will bounce onto the floor and hide and break your heart.