I had a Safari problem on my iMac 2003 running Tiger 1.4.11 Safari kept crashing, so I found some advise to run font book then run Font Nuke. Running this program basically rendered my computer useless, because I tried to back a file I needed on CD while the program was running for about 3 days, and it crashed.
So, I ran the program again and did not touch it for one week. It was updating the list and last count was over 1,000,000 caches. I had screen saver running, but nothing else.

I went this morning and there was message application has closed, to you want to reopen.
So now back where I started, Is there something I'm doing wrong?

It had lost all that updating data. PLEASE ADVISE-THANKS

By the the way All my other applications were running fine including FireFox, just Sarafi was giving me problems.