The third one you have might be payment protection insurance or PPI. It is a bit scandalous at the moment and pls do check with your insurance broker to see if you have been mis-sold as there are lots of complaints recently regarding non-pay-out PPIs.
Home insurance is normally compulsory as your mortgage lender will need it to protect their own interest in your property. Life insurance is probably necessary BUT it all depends. If you take out the mortgage alone, there is no point taking such insurance as you wouldn't be worried if passing away

It is necessary when you have someone with you, husband/wife/children and you don't want them to lose out should worst thing happen.