Statutory is Tax free. Pay in lieu of notice is taxable as if it was salary. Everything else depends on the number of years service you've done, whether or not you have taken a tax free lump sum for redundancy in the past and whether or not you intend to take one from your pension in the future. Your employer should give you both options (Take a tax free sum or don't) so you can make an informed decision.
In my experience as the employer, staff closer to pension age with a decent pension pot were less likely to take the tax free redundancy option