Okay, this happened to a friend and I. Safari just suddenly stopped working for us. It acted like it was loading the page, but it never actually displayed anything. It would just hang there and do nothing. Another hint that you might be having this problem is when you load up your Console (in Applications, Utilities), you get error messages like:
2003-12-28 02:35:42.830 Safari *** -[NSCFString characterAtIndex:]:
Range or index out of bounds
2003-12-28 02:35:43.766 Safari ***NSTimer discarding exception
'*** -[NSCFString characterAtIndex:]: Range or index out of bounds')
that raised during firing of timer with target 192c670 and selector
This seems to happen after installing Windows True Type fonts on your Mac. I'm not exactly sure what about the fonts caused Safari to explode, but I seem to have found a way to fix it.
Basically, you just go into your Safari preferences and change the font, and then you can change it back after you can see that Safari will load pages again. It appears that the default font that seems to cause trouble is Times. You might be using something else, but it's a worth a shot to try this anyway. If it won't let you change the font in Safari (it wouldn't let me do this), you can go into Font Book under Applications and temporarily disable the font. Then open up Safari and it should be using a different font (Helvetica for me). Then it started loading pages again for me.
Of course, if you liked Times better, you can then go back, reenable Times, and set it back again. I did this just fine, and am currently using Safari with the Times font again. Everything I wrote here worked fine for me, but I have yet to see if it'll work for my friend.
This seems like an issue related to one particular font; I have several Windows TrueType fonts on my machine, and Safari is working just fine ... but it does point to the subtle nature of font problems -- it's odd to connect a page not loading with a font issue; you'd think the page would just load with a default font instead.]