You can't avoid the taxman. Inheritance tax, if any, will be paid before you get it.
Sorry, I don't do general investment advice. For that sort of sum you probably need to consult an IFA if you've next to no knowledge or experience. He will be able to shield some of the income from tax.
It's the basics initially - use your ISA allowance for tax free savings and investments. After that, as dzug says, seek advice - www.unbiased.co.uk will give you a list of IFA's.