I have recently update my desktop with new updates. But after upgrading it to new kernel version, firefox doesnt show my bookmarks, even when I open any link in new tab it doesnt show link in address bar.

New kernel version - 2.6.24-19-generic
firefox version - 3.0

You can probably still boot into your old kernel using the GRUB menu. I suggest you do so and see if the problem goes away. This will verify whether the problem is really the new kernel or something else so you (and we) aren't looking in the wrong place for the trouble.

By default (if they haven't changed it in the last few versions) Ubuntu does not display the GRUB menu. But if you press the escape key immediately after the computer finishes its power-up tests you will see the menu. Hopefully both the old and new kernels will be displayed. You can use the arrow and enter keys to select which to boot. Be aware that the menu probably has a fairly short timeout that will select the default if you don't press any keys.

I did check with older version and it is working with that. that i why i posted that with my new kernel version firefox behave's weird

Anyway for time being i have installed opera and started my work.

Try this...

Copy the old profile folder ~/.mozilla/firefox/xyz.default in its entirety to the same location with a new name - for example, ~/.mozilla/firefox/xyz.newdefault.

Edit the profiles.ini file (located in ~/.mozilla/firefox) and replace the old profile folder name with the new one.

When you run Firefox again, the bookmarks, address bar, etc should all be working again.

(If you re-edit the profiles.ini file and put the name of the old profile folder back into it, the problem will come back.)

It is better to state such things explicitly in the original post. When trying to help people onf on forums like this, the OP's level of experieince and knowledge is not always clear. And even experienced people have their lapses.