In answer to your question, my understanding is that there is no legal obligation to have any of the insurances you list, but they are often a good idea (especially buildings cover)
However, in saying that...and I don't want to contradict the professionals on here, but I would have thought that trying to maintain a minimum level of Building insurance, if at all possible, would be fairly essential. Fair point that mortgage protection (what good is it doing you?) and life policies could go without any real impact, as could the contents part of your building and contents insurance. Given the equity in the house and the possible need for re-build in the event of a fire, I would thought Building insurance was essential. By only insuring the building of your home, you could reduce your €57 per month. You should also shop about, because if your mortgage provider sold you the house policy @ €57 per month, it's probably relatively expensive and you could almost certainly get a better deal elsewhere. I wouldn't know who to send you to, other than to say shop about and try comparison sites etc.
In my opinion, whilst the mortgage co may have insisted on life cover etc when you took out the mortgage, there is little they could do to stop you cancelling it at this stage. The saving of your two life policies, plus MPI and a saving on your house insurance might make things a lot more bearable and help your case with the bank.
On a different note, you may also want to look into your Mortgage Protection Insurance. If it was taken out to insure you against illness and inability to work, then why is it not paying your mortgage now? If the policy was taken out when you were working and you then became unemployed (and haven't claimed), or was taken out incorrectly from the start, then you have been insuring something that wasn't insurable and as such may be entitled to a refund for any amounts paid in error. Not know exactly what your policy covered, I can't say for sure, but in the case of a girl I used to work with, her husband (self employed Architect) closed up after the crash and had to go on the dole, he tried to claim on his mortgage protection insurance and found out he couldn't, as he had been self-employed and not an employee (his policy only covered employees). However, it also meant that the insurance company hadn't been insuring a risk, so he got a refund (several thousand euro) of all premiums paid while he was registered as self employed. Anyway, just a thought