Unfortunately, you have to utilize sysobjects/syscolumns to retrieve the ids in order to get the description data:
SELECT u.name + '.' + t.name AS [table],
td.value AS [table_desc],
c.name AS [column],
cd.value AS [column_desc]
FROM sysobjects t
INNER JOIN sysusers u
ON u.uid = t.uid
LEFT OUTER JOIN sys.extended_properties td
ON td.major_id = t.id
AND td.minor_id = 0
AND td.name = 'MS_Description'
INNER JOIN syscolumns c
ON c.id = t.id
LEFT OUTER JOIN sys.extended_properties cd
ON cd.major_id = c.id
AND cd.minor_id = c.colid
AND cd.name = 'MS_Description'
WHERE t.type = 'u'
ORDER BY t.name, c.colorder
You can do it with info-schema, but you'd have to concatenate etc to call OBJECT_ID()