Hulu uses Flash for video so the problem might be that Flash is crashing and taking the browser with it.

Update your Flash would be a good place to start. You can use Mozilla's plugin check to do so.

That link is no good. Do you have another?

Your plugins list shows outdated plugin(s) with known security and stability risks.

# Shockwave Flash 10.0 r32
# Next Generation Java Plug-in 1.6.0_17 for Mozilla browsers 

Update the Java and Flash plugin to the latest version. See http://java.sun.com/javase/downloads/index.jsp#jdk (you need JRE) http://www.adobe.com/software/flash/about/ --- Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of your add-ons is causing your problem (switch to the DEFAULT theme: Tools > Add-ons > Themes). See Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems and Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems

I can't update Acrobat or Flash for some reason. Firefox says I have a missing plug in called "gp.xpi". It has downloaded and tried to install and windows does not recognize it. Quicktime won't install either, it freezes and does nothing once the status bar comes up in its window. I'm attempting the Java download now, and I'm crossing my fingers for it to work. I'm at the point of just backing everything up and reinstalling Vista. This isn't the only issue I'm having at the moment.

Alright! I uninstalled flash player, rebooted, and installed it again. Hulu is now working, finally. Thank you guys so much for your help! :D