Uninstall 10.5.3

Hello everyone.

I downloaded and installed the 10.5.3 update today... In the beginning I was excited because it would solve some issues I was having with the graphics card (or something else, I don't know) that used to make my computer to display text very strangely on many applications. They told me it was a very common thing among MacBook Pro users and that it was gonna be fixed on this update. Anyway, I have no idea if it got fixed...

But, even though my Wi-Fi connection wasn't the best before the "update", it was waaaaaay better than it is now. I used to have some interruptions, but right now it's almost impossible for me to use my Internet. It's almost disconnected from the router all the time... Whenever it's not (10% of the time) it is sloooooow as heeeell... It takes me literally a few minutes to open a simple web page.

Anyway, I hate this so-called update and I wish I had never installed it.

I tried unplugging my router and left it off for half an hour. Meanwhile I removed the wireless's profile and restarted.

All that to find out that it still doesn't work... If I get closer to the router it works great, but on my desk it's impossible to get a signal. And sure, a lot of people will say "well, get closer the the **** router!"... but I need it to work all the way here... And it was working fine, before the update!

Can somebody tell me how to uninstall it?? Thanks!!