Have been experiencing this for a while on XP Pro. I have now discovered what is causing it. It's Adobe Reader or at least the plugin for reading PDF files in FF or IE8.
Solution is to update reader to 9.1.2 using updates and viola instant start of FF and IE8, phew.
Please no lectures on using Foxit, I have that too.
Tim
ZeN & freenetname
ST546v6 on 8 Meg Active
Check my bad boy speeds out on ZeN