To have websites with id = 1 and 604 on top of list, you need to alter your ORDER BY clause like this:
SELECT
in_website_id, in_website_type_id, vc_website_name, vc_login_name
FROM
dbo.website
WHERE
bt_active = @bt_active
ORDER BY
(CASE WHEN in_website_id IN (1, 604) THEN 0 ELSE 1 END),
vc_website_name