I have this issue from MANY Ubuntu releases.
why when I wget
a file it takes just one row and give me all information (like time, total space, bit downloaded, percent)
When downloading flashplugin via flashplugin installer, the installer in a terminal displayed many rows - why?
That's by design of the installer. These commands are executed by the flashplugin installer post-installation script:
The relevant setting is
progress = dot:default
which cannot be overriden. Perhaps you can file a wishlist bug for that on https://launchpad.net/ubuntu/+source/flashplugin-nonfree/+bugs