hm, first you need to decrease the TTL to an absolute minimum, to force any caching DNS servers to refrsh their databases more frequently. Then you need to move your DNS file(s) to the new server,...
Or you can use 'find' and pipe the output to the 'xargs rm' rubin provided.
but since these files most likely are database files you might want to consult your local dba if he/she for some reason...