My wife and I bought a house in 2006 for £170,000 on a two-year fixed-rate mortgage of 4.99 per cent. This reverts to a standard variable rate of 7.25 per cent next month, at which point we will have about £50,000 still outstanding on the loan. We could pay off the loan altogether by selling some non-Isa unit trusts, while staying within our annual capital gains tax allowances. We have made some good gains recently on £135,000 of what are risky investments. Should we pay off our mortgage as soon as possible, or should we leave the money in the funds?