azertywarrior12's solution worked for me, too, using the Cinnamon desktop, but I could only zoom into the left half of my wide-screen laptop monitor. It was this way on Mint 12 and now with Mint 13.
Now, there is a solution that actually gives you REAL alt-mousewheel zoom under Cinnamon, thanks to an update from Tobias Quinn to his package gnome-shell-mousewheel-zoom. It's not in the Mint repos (yet) but you can add a PPA or download the .deb package and install it. (I did the latter.) Here is a link to the instructions on Launchpad. https://launchpad.net/~tobias-quinn/+archive/gsmz
I tried to enable screen magnifier feature on my linuxmint nadia cinnamon 64bit. It worked but I lost the nice looking login. I've installed the package https://launchpad.net/~tobias-quinn/+archive/gsmz
while installing it asked me to configure options from mdm/gdm I chose mdm. After the installation I logged out and tried to login. The total look has been changed.
I installed the .deb package named "gnome-shell-mousewheel-zoom_0.8.0-0ubuntu3_amd64.deb" and that informed me that it is going to remove 1 and install 2 packages.
I have completed the installaton proccess.
How could I restore the previous settings?
It might be defcon or something similar to it
When I installed and logged out it caused trouble logging in and after reboot I was able to login and that time I shocked with the very uggly looking login screen. The cinnamon native login screen was disappeared.
Somewhere I've found a message during logging in or out saying to check or editing config file to login.
I like original cinnamon desktop settings. So please help me get back my previous desktop settings.
Thanks in advance.