Hi @ashgard,
could you try uninstalling the node wizard and installing it again using the latest version? (using this update site http://update.knime.com/analytics-platform/4.2/). This worked for me. Maybe there is version mismatch in your case. To start KNIME from eclipse you can just right click on the KNIME Analytics Platform.launch file and select Run As -> Knime Analytics Platform. This should automatically use the right configuration for starting KNIME.
Cheers,
David