The Ubuntu installation on my Dell Precision T4600 (bought on 2012.06) worked just fine - besides one thing - touchpad left button. When I've tried to select text or drag window I needed to wait about one second before cursor has changed to "hand icon". The solution is, to disable, or change delay for third mouse button simulation - so far so good... but there is no such option. In my case helped something that does not make sense, but it has worked.
Just execute those two commands:
sudo apt-get install gpointing-device-settings
This installs and starts the mouse settings application - there is no need to do any changes, it probably overwrites some config files and problem was solved - at least in my case.
Problem is related to this ubuntu bug