if your card is removed,then have you edited /etc/X11/xorg.conf driver to onboard gfx card ?(intel???)
also,there is not much any settings specific to nvidia except changing the driver in xorg.conf.
you may like to remove nvidia driver later(sudo apt-get remove --purge nvidia-glx-new nvidia-settings).
I think you should boot without usplash and quiet option.
for that when your pc boots,select from grub,gutsy option=>press "e"=>select "kernel /boot/vmlinuz...." line=>press "e" again.now browse into the end of that line.
remove "quiet splash" options by backspace.
Press ENTER.Press "B" to boot.
when system finishes booting,press CTRL+ALT+F2 and login into a pseudo terminal.
then,run "sudo dpkg-reconfigure xserver-xorg"
select intel as driver.give the Displays horizontal and vertical freq if u know that.
now do this:
"sudo dpkg-reconfigure linux-image-`uname -r` "
that will solve hopefully.also,firefox font rendering problem will be solved with intel drivers as that workaround is for drivers except ati and nvidia propreitary drivers.
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