I keep bank statements, receipted bills etc. for the length of time that the tax authorities can demand an audit, plus one or two years extra.
When I have done my year's Income tax and put all the papers in a large envelope, I write the year on the outside and throw out (read destroy) the oldest envelope when I put the new one away.
I haven't need any of it yet, but you never know, do you?
So sorry to hear about your husband's death, Georgesgran.
I find Internet banking an absolute boon and very safe, plus got the bank to check my budget figures when we had lived in this house a year, and have an account that all bills are paid from by direct debit. A twelfth of the annual total needed goes into that account each month and I regulate that amount at the end of each year.
It really has given me peace of mind, as I know the money to pay the bills is there!