Firstly - it doesn't happen on my system, which, like yours, is XP SP3 (XP Pro by the way, you don't specify) with all the updates.
What do you mean when you say Windows crashes? Blue screen? Reboot?
Have you tried this creating new folders/renaming folders on a share on another Windows system?
It's doubtful that it would be a driver - there is no drivers specific to the DNS-323 - it does go through your network stack so it will use the network card driver, etc., but if that were the cause then I would expect crashes in the test I suggested above.
Even though the DNS-323 is running linux, Windows does not really know that it is not talking to another windows system, because of the SAMBA daemon running on the DNS-323 - it's not completely transparent, but most of the issues are known and repeatable and I believe relate to permissions and attributes.