It is possible for those with low levels of pension savings to take their pension as a lump sum. These are the 'trivial commutation' rules and they allow those with total pension funds worth no more than 1% of the current lifetime allowance to be paid as a lump sum.
The current lifetime allowance is £1.8 million and so this would apply for those with pension savings of £18,000 or less.
However, the link with the lifetime allowance disappeared from 5 April 2012 when £18,000 became the maximum allowable figure.
There are other requirements that need to be satisfied but this is the most important.
I don't know the value of your wife's pension, but if it is greater than £18,000 then it cannot be paid as a lump sum under these rules. However, as her pension is from the county council, it is likely to have some guarantees and future escalation built in. If that is the case, then the total fund value required to provide a starting pension of £800 each year would be significantly more than £18,000.
I recommend that your wife seeks independent financial advice to make sure she can't claim the lump sum, but if my assumptions about the value of her pot are correct that seems unlikely.