Uma
I am surprised that setting the preferences has not worked.
It always works for me on my eclipse and RAD(and other eclipse based tools like WID).
The file(org.eclipse.ui.ide.prefs) is where these preferences are persisited in teh file system.
Look for this under this directory
\configuration.settings\org.eclipse.ui.ide.prefs
I am not showing the entire file here (as that is just a clutter). Look at the SHOW_WORKSPACE_SELECTION_DIALOG and ensure that it's value is true.
MAX_RECENT_WORKSPACES=5
SHOW_WORKSPACE_SELECTION_DIALOG=true
eclipse.preferences.version=1
HTH
Manglu