If I opt out of the Teachers Pension Scheme, will the 'deduction to TPS' shown on my pay slip go to me?

Provided this is something that is coming out of your salary (rather than an additional employer contribution towards your pension), you would get most of this money (depending on your tax rate). There are tax/NI benefits to paying into a pension scheme (not sure of the exact figures but you either pay less tax/NI on your pension contribution or none at all) so if you chose to opt out of the pension scheme, you wouldn't get the whole amount that you pay into the pension scheme as you would be subject to full tax/NI contributions on it. Your payroll section should be able to advise you on the figures.