Changing battery

Our 2002 1.6 new beetle is just over 3 years old and I figure it may be cheap insurance to change the battery over before it fails. Does anyone know if it is necessary to maintain electrical power to the car (thru the cigarette lighter) from a 12v power source whilst removing the old battery. I've read that if power is fully removed and then reconnected you can have driveability problems.
Also another question - is it only in Australia that they use fully synthetic oil in the engine or is it world-wide. Thanks.:aus:

Found the answer in the owners handbook where it makes no mention of an external battery. However the Haynes manual indicates you need an external battery plugged into the cigar lighter socket to maintain codes and avoid driveability problems.

no, the only real problem you run into on the new beetles when changing the battery is the radio. if you leave the key in the "on" position while you change the battery, it puts your radio in safe mode. even in some cases when you change it with the key in the "off" position, if you leave it without battery power for an extended period of time, it will still go into safe mode. the best way to do it is to make sure the key is out of the ignition, change the battery out quickly

Thanks Jackdaniels 386 - I'll follow your advice and put the key in my pocket and make sure the changeover is quick.
Regards Denis