Hi,
I had this problem as well and I'm running an ATI graphics card.
The bug is described here -
https://bugs.launchpad.net/stellarium/+bug/525995
The last entry is -
"Jarda Kristen, could you please download the test build from here:
https://launchpad.net/stellarium/+download
And report if there is a difference?
If some of the text in the test build is unreadable, try the following: in Stellarium's configuration file (config.ini), under "[main]", add the following line:
use_qpaintenginegl2 = false
Then save the file and restart Stellarium.
(On Windows, Stellarium's configuration file is accessible through Stellarium's folder in the Start menu - just look for "config.ini".)"
I did this and all is fine now.
Ian