UK and Ireland are not in Schengen, Harry!
Really? Have a read of 2004/926/EC: Council Decision of 22 December 2004 on the putting into effect of parts of the Schengen acquis by the United Kingdom of Great Britain and Northern Ireland:
Article 1
The provisions referred to in Article 1(a)(i), (b), (c)(i) and (d) (i) of Decision 2000/365/EC shall be put into effect for the United Kingdom as from 1 January 2005.
The provisions referred to in Article 5(2) of Decision 2000/365/EC shall be put into effect for Gibraltar as from 1 January 2005.
The provisions of the acts constituting developments of the Schengen acquis adopted since Decision 2000/365/EC and listed in Annex I of this Decision shall be put into effect for the United Kingdom and for Gibraltar as from 1 January 2005.
The provisions of the acts constituting developments of the Schengen acquis adopted since Decision 2000/365/EC and listed in Annex II of this Decision shall be put into effect for the United Kingdom as from 1 January 2005.
There are no certain opt-outs with regards to Schengen.
The EU seem to disagree with you:
The participation of Denmark
Although Denmark has signed the Schengen Agreement, it can choose whether or not to apply any new measures taken under Title IV of the EC Treaty within the EU framework, even those that constitute a development of the Schengen acquis. However, Denmark is bound by certain measures under the common visa policy.
europa.eu/legislation_summaries/justice_freedom_security/free_m ovement_of_persons_asylum_immigration/l33020_en.htm