Hardware: dual core Intel.
OS: Windows Vista SP2.
Shareaza version: 2.4.0.0
Nature: infrequent and intermittent; severe.
Sometimes Shareaza causes the system to freeze for up to tens of seconds at a time, repeatedly, until shut down and restarted. The freezing continues, diminishing, for quite a while after Shareaza is closed, which is especially odd. Setting Shareaza's priority to Below Normal and forcing it to only use one core does not do more than slightly mitigate it.
This seems to mainly happen when searching -- not when just downloading or uploading, or idle and connected, or idle and not connected. It seems unrelated to hashing, happening when no hashing is going on.