Windows 7: Slow Browsers Startup

Hi, Recently I have noticed that IE9 and Firefox 5 take a really long time to load up on startup, whereas Opera loads up instantly on startup. I have tried disabling all add-ons for both these browsers, as well as disabling all startup entries to see if these have an effect. I have also ran CCleaner, defragmented my hard drive and registry as well as cleaned them. There isnt a problem with my windows 7 startup as it is usually loaded fully in 5 seconds of the welcome screen, with all startup entries enabled, there just seems to be something clashing with both these browsers on the first startup, after the first startup these browsers load instantly within clicking their shortcuts. Help please!

Do you remember any plugin installation like DivX in the near past?

yes, I have divx vod helper plug in enabled in firefox and divx browser plug in object enabled in internet explorer, I'm going to disable them and see what the outcome is

Disabled all Divx Addons but problem still persists

for firefox i can reccomend speedyfox, it works, you have to run it now and again when you see firefox start to slow up.
SpeedyFox - Boost Firefox in a Single Click! | CRYSTALIDEA Software

I already have a program called firefox preloader and that still hasnt helped. I just don't understand when opera and chrome load instantly yet these two take forever on their first start up!

TY