Revert from Firefox 2 Visual Updates

I dont know how you feel but I really didnt like the Firefox 2 visual updates named as FX2 Visual Update/Default Theme Update by Mozilla and you can see that they have put a lot of effort into this. The only thing I liked is the glow around the feed button in the address bar
I was expecting Mozilla to include the old theme along with Firefox 2.0 so that those who liked the Classic version would switch to it but they didnt. There is not much to worry about because it is Firefox not IE. There are some hacks and a theme which allow your FF 2 to look just like FF 1.5

Initially to change the look of icons to Firefox 1.5 use this theme

Tip: Theme files (and Extensions) can be saved to the harddisk(instead of installing it) by Right clicking on the download link and selecting Save Link As option. The theme can be installed later on by dragging the .jar file into the Add-Ons window of Firefox

Then there are a few more things which you may not like. Im not forcing you, change if you want to

For all the hacks below you need to open about:config in Firefox (Just type about:config in addressbar and press enter)

The first one that irritated me the most was the Close button on every tab and no common Close button for tabs like in 1.5 then the Tab scrolling and the easy-to-read list of all your open tabs was no relief either.

• Common Close

To remove individual close button for each tab and display a common close button like in 1.5

change browser.tabs.closeButtons to 3

• No Tab Scrolling

change browser.tabs.tabMinWidth to 0 (zero)

• Remove Easy-to-view list

Add

/* Disable Container box for "List all Tabs" Button */
.tabs-alltabs-stack {
display: none !important;
}

to userChrome.css

This file sets the display rules for various elements in the Firefox user interface and is located in the sub-folder called chrome in your profile folder. This file does not exist by default, so you need to create it before you can start adding your preferences. There’s actually an example file that exists by default, called userChrome-example.css. Basically, you can just rename that file by removing the -example part

To know more see this Mozilla help page