This query will generate script to change schema name for all the tables:
SELECT 'ALTER SCHEMA dbo TRANSFER ' + s.Name + '.' + p.Name FROM sys.Tables p INNER JOIN
sys.Schemas s on p.schema_id = s.schema_id WHERE s.Name = 'oldschemaname'
this second is for stored procedures:
SELECT 'ALTER SCHEMA dbo TRANSFER ' + s.Name + '.' + p.Name FROM sys.Procedures p INNER JOIN
sys.Schemas s on p.schema_id = s.schema_id WHERE s.Name = 'oldschemaname'
First you will alter all these objects and after this delete the schema.