If I understand you correctly, when you run the launcher opera opens 2 tabs.
To avoid this, in opera "Settings > On startup" set it to "Open the start page".
When using Ubuntu you could also add a quicklist to your normal opera launcher.
Copy the opera launcher from /usr/share/applications to ~/.local/share/applications
and add a quicklist as in this example... http://ubuntuforums.org/showthread.php?t=2178491&p=12806948#post12806948
