Agreed, a trigger is not at all the best place for this type of thing.
RECONFIGURE is not allowed to be part of a transaction. A modification trigger is inherently part of a transaction. So, RECONFIG is impossible in this context. Thus, you may have to enable the options permanently.
Also, it's best to avoid all excess overhead in triggers, including declaring unnecessary variables. Thus, maybe something like this:
CREATE TRIGGER tr_ORS_CostDrvAfterInsert
ON dbo._tmp1
AFTER INSERT
AS
SET NOCOUNT ON;
declare
@responseText varchar(8000);
exec [dbo].[sp_ORS_MS_Request]
'http://MyURI.php',
'GET',
'',
'Method',
'',
'',
@responseText output;
SQL DBA,SQL Server MVP(07, 08, 09) A socialist is someone who will give you the shirt off *someone else's* back.