Hi there -excuse me for any non-technical talk. I have a Draytek 2820 and also a 120. I have two ADSL feeds (one Zen & one O2) and want them both to be distributed by the 2820 according to the demands on my network. Is there a step-by step guide to achieving this available? Many thanks...

check this guide, should be similar to your model
http://www.draytek.co.uk/archive/kb/kb_load_balancing.html
http://www.draytek.com/index.php?option=com_k2&view=item&id=5181&Itemid=293&lang=en
also if you perform a search in the forum "load balance" should bring many results