For Indexes, TOAD will run a query on the SYSCAT.INDEXES view. I suspect your userID does not have access to this view. In the editor try running "SELECT COUNT(*) FROM SYSCAT.INDEXES" and see what the results are.
For the script tab of a table or object I believe TOAD is using db2look to get the ddl. If that is correct then SELECT privilege is needed on the system catalog tables.
Thanks,
Eric Sheridan