What are the main differences between Analogue Camcorders and digital?
I am thinkig of changing.

Answering a question like this is impossible without investing much
time and work. You might want to have a look at the Google Answers
pricing guide:
http://answers.google.com/answers/pricing.html

http://www.mightycoach.com/articles/videotips/01-digitalvsanalogue.html
http://www.noelleeming.co.nz/wcsstore/articles/NoelLeeming/product/Camcorders.html

Most basic answer is that digital has much better quality in terms of
picture and often sound.

This is probably the best to sum it all up:

http://www.eco.utexas.edu/Homepages/Faculty/Norman/ECO361N.DailyOld/Video.Editing/article.htm

well first of all anolog cameras give much higher quality. A digital
camera splits the image up into many tiny tiny tiny pixels and then
maps them out. Obviously theres going to be some loss of quality when
you cut something into tiny pieces, just like with records compared
CDs (although i hate the crackling of records). The only advantage to
a digital camera is the ease in which you can duplicate an image; as
many times as you want, any size you want, without having to visit the
photo-mat. Although you have to consider the fact that digital cameras
will on-the-fly process light and change levels, something you'd have
to be a photographic engineer to do on your own with an anolog camera.
Its a toss up... I wouldn't throw one out for the other. If you can
fit the huge old-school cameras in your luggage, stick with it, if you
need to put something the size of a deck of cards in your pocket to
take pictures with, go digital.