No. In common with other pre-Youview Humax recorders your recordings will be retained.
The option to avoid if you do not want to lose your recordings is the 'format' option.
But a default setting is unlikely to address the freezing issue either.
With the 9300T the two commonest causes are
1) Mistuned to a weaker transmitter causes picture freezes.
2) Using old software can cause the menus/remote to freeze.
See this ‘fix’ for further details http://www.howtomendit.com/answers.php?id=452365
NS, July 2012