only security updates
 

Is there a simple way to have my now testing distro only have security updates downloaded when I do apt-get dist-upgrade?

I actually only want security updates and updates for particular programs I choose (apt-get --reinstall). But so far I managed only to get updates for the whole system.

I suppose you only want to have these lines:

• deb http://security.debian.org/ sarge/updates main
  deb-src http://security.debian.org/ sarge/updates main

But it will not give you the reinstall option, the sources need to be there in your sources.list. You could try to use the HOLD PACKAGE feature with dselect (see man dselect) or use synaptic for easier management.

AFAIK, there are no security updates for testing, which is Woody's main advantage. In order to get a security update for testing you need to download the package from unstable.