Option 1
SELECT
sysobjects.Name, sysindexes.Rows
FROM
sysobjects
INNER JOIN sysindexes
ON sysobjects.id = sysindexes.id
WHERE
type = 'U'
AND sysindexes.IndId < 2
ORDER BY
sysobjects.Name
Option 2
SELECT OBJECT_NAME(OBJECT_ID) TableName, st.row_count
FROM sys.dm_db_partition_stats st
WHERE index_id < 2
ORDER BY st.row_count DESC
Reference
http://www.mssqltips.com/sqlservertip/2537/sql-server-row-count-for-all-tables-in-a-database/