You can copy folder "%APPDATA%\Quest Software\SQL Navigator x.x.x" (for instance "C:\Documents and Settings\vliu\Application Data\Quest Software\SQL Navigator 6.0.0") to the same location in your new PC. Then export registry folder "HKEY_CURRENT_USER\Software\Quest Software\SQL Navigator x.x.x" and import it into your new PC as well. After they are done, start SQLNav in your new PC. It should have all the stored settings including connection details.
Please be aware that this action will overwrite the settings in your new PC. You should backup the folder and registry folder in your new PC before performing this action.
Backing
up Sql Connections proper way