  We present the performances of two 92% enriched $^{130}$TeO$_2$ crystals
operated as thermal bolometers in view of a next generation experiment to
search for neutrinoless double beta decay of $^{130}$Te. The crystals, 435 g
each, show an energy resolution, evaluated at the 2615 keV $\gamma$-line of
$^{208}$Tl, of 6.5 and 4.3 keV FWHM. The only observable internal radioactive
contamination arises from $^{238}$U (15 and 8 $\mu$Bq/kg, respectively). The
internal activity of the most problematic nuclei for neutrinoless double beta
decay, $^{226}$Ra and $^{228}$Th, are both evaluated as $<$3.1 $\mu$Bq/kg for
one crystal and $<$2.3 $\mu$Bq/kg for the second. Thanks to the readout of the
weak Cherenkov light emitted by $\beta/\gamma$ particles by means of
Neganov-Luke bolometric light detectors we were able to perform an
event-by-event identification of $\beta/\gamma$ events with a 95% acceptance
level, while establishing a rejection factor of 98.21% and 99.99% for $\alpha$
particles.
