Safe Boot is the standard Mac way to verify and repair your disk
http://docs.info.apple.com/article.html?artnum=107392
However, I'm recently seeing some temporary freezing problems that happen when verifying a file (with 10.4.3 on an iBook). Safe boot and permissions repair fixed that last time.
Maybe it's related, but I'm not a coder.
Anyway, more info needed. Check the permissions on your Save folder, for starts.