No, it's much easier: simply put a firefox shortcut into the "Startup" folder located into your [Start menu]>Programs EDIT: if your default browser is firefox you can make it even open a custom webpage on startup by adding a shortcut to an URL in the above-mentioned folder. Cool, huh?
You can also open a bunch of TABS and then open a page in one and make it your *Homepage* then go to the next tab and do the same so you end up with a bunch of pages already loading when you launch Firefox.. I have 5 of the sites I use the most loaded as soon as FF is up and running..