To access values in the widget parameters box ( the mysterious text input below the widget drop down in dbasis), in your widget script you have to access the $plugin_info['params'] array. It will have a hash of your key=>value pairs which are semicolon separated.
Example:
in the mystery text box your have
'watch=topic;relid=29'
in your widget script you can get the values via:
$watch = & $plugin_info['params']['watch'] ;
$relid = & $plugin_info['params']['relid'] ;
This sounds like something that should be in the syntax wiki...
-Oscar
OK, how about the blog instead?