OK
Ran more tests today. Interestingly the speed is up without doing anything, but still much lower than sold.

I got 6.5Mb/s and 1.9Mb/s... Still not as fast as my old BeThere (now Sky) and below advertised.

I then tried to test directly through the VM router/modem in Modem Mode... That failed. It would not work so I switched it to Router mode. This time the test showed the full speed, almost.
29Mb/s and 1.9Mb/s

As you can see the Upload speeds are almost identical and seem to match that advertised by VM. The Download speed, whilst not quite the advertised speed is almost there, so this is a settings issue. Next question is what is the issue?

I am on the latest SW for my Router.
Model Name : Vigor2820Vn
Firmware Version : 3.3.7.3_232201
Build Date/Time : Sep 13 2012 19:09:39
ADSL Firmware Version : 232201_A Hardware: Annex A

So it is not that.

I have the "Physical Type" set to "100M full duplex" a suggestion of Draytek. I had it on "Auto negotiate" before. I tried doing both back and forth, made zero difference.

QoS is on. Tried it with QoS off and got the following speeds:
30.9Mb/s and 1.9Mb/s So the issue is QoS.
Trouble is I need QoS as I run voice over my LAN/WAN.

So any ideas. What is the solution to this?

A newer version of the firmware is out version 3.3.7.4. Your issue isn't listed as one of the fixes but it's worth a try.
What values did you have qos set at?