I don't know much about Windows internals, but I do know that disabling the paging file, especially on a system with 1GB of RAM, is generally a bad idea.
The paging file is used as an "overflow" for RAM. Without it, your computer will just freeze and crash if you run out of RAM. While the paging file is much slower than RAM, a slight decrease in performance when your system is running out of memory is definitely better then your system just crashing whenever you open Firefox.
The paging file is also a good place for your system to stick stuff that needs to be loaded, but isn't actively being used, making more room for more important stuff to be loaded in memory.