Launching from CD

Did you MD5 test the ISO you downloaded?
Did you burn the CD as SLOWLY as you could?
Did you test the CD for defects once initially booted to?
Have you tested your RAM for errors?

May be your Ubuntu live install cd is not perfect or it can't be read from your cdrom drive please verify it...

Here some general note on install Ubuntu and howto to get a good ubuntu iso cd image (.iso) to burn on a cd:

- Here the steps to install Ubuntu 10.04.1 https://help.ubuntu.com/community/GraphicalInstall

- Here install Ubuntu video http://www.youtube.com/watch?v=XaqaDZZ_P0g&feature=fvw

Below there are some intructions to:
--- 1) Ubuntu prerequisites... and Ubuntu for pc with low power
--- 2) download the iso...
--- 3) check the md5sum of the iso image, please don't forget to check...
--- 4) burn the iso image to a cd ...
--- 5) install Ubuntu using the self made cd ...
--- 6) trouble screen at installation or at first boot after installation ...
--- 7) Ubuntu manual and online help...
--- 8) Relax and fun...

The main ubuntu site is this: www.ubuntu.com and the download location is this
http://www.ubuntu.com/desktop/get-ubuntu/download

--- 1) Ubuntu prerequisites: https://help.ubuntu.com/community/Installation/SystemRequirements

Ubuntu 10.04.1 release notes: https://wiki.ubuntu.com/LucidLynx/ReleaseNotes

https://wiki.ubuntu.com/LucidLynx/ReleaseNotes/ChangeSummary/10.04.1

If your ram is less than the recommended amount, you won't be able to install with the graphical installer,
but you might be able to use the Alternative cd, where you can use a text based installer - that uses less memory.
If your machine does have plenty of ram, you might want to try running Memcheck (which is also an option from the live cd, see below)
to just make sure your ram isn't failing.

- if your pc doesn't meet the Ubuntu prerequisites, you can try:

xubuntu http://www.xubuntu.org/get
lubuntu http://lubuntu.net/blog/lubuntu-1004-now-available-download

here a list from distrowatch: http://distrowatch.com/search.php?category=Old%20computers

- if you pc is a very low resource pc you can try different Linux distribution something like:
 DSL http://www.damnsmalllinux.org/
 Puppy Linux http://www.puppylinux.org/
 Slitaz http://www.slitaz.org/ : Slitaz 3.0 release note http://www.slitaz.org/en/doc/releases/3.0/relnotes.en.html

1.a) Please always prefer to download them using torrent if you can...

1.b) BE ABSOLUTELY SURE to verify the md5sum https://help.ubuntu.com/community/HowToMD5SUM
of the downloaded iso image BEFORE to burn it

1.c) burn it using infrarecorder if you are using Windows at lower speed you can do

1.d) boot your pc from cd and install...

--- 2) please download the 700 mb file http://www.ubuntu.com/desktop/get-ubuntu/download simply press on download button
To avoid download errors download the desired ubuntu iso install cd image using the torrent protocol.

- if you are using Windows please install a torrent client i suggest you http://deluge-torrent.org/
and download the iso using a .torrent link from here:
http://releases.ubuntu.com/10.04.1/ubuntu-10.04.1-desktop-i386.iso.torrent

--- 3) PLEASE BE SURE TO CHECK the md5sum of downloaded file to be sure it have no error https://help.ubuntu.com/community/HowToMD5SUM
Only if the md5sum number match with this: http://releases.ubuntu.com/10.04.1/MD5SUMS go to the next steps.

--- 4) burn the iso image onto a cd, to do it install and use http://infrarecorder.org/?page_id=5 burn the cd at lower speed you can do and activate the data verify

--- 5) insert the self made install cd into your pc cdrom drive and reboot your pc. YOU MUST NOT SEE Windows starting and you can try Ubuntu from cdrom and then install it

--- 6) If you have trouble with installation (the system freeze or you can't complete it) be sure to read the above suggestions, then:

Please boot entirely (you must not see windows starting) from Ubuntu live install cd and when the system start to boot from cd you will see two bottom screen icons (keyboard and man inside circle ) please press space (choose your desired language) then a screen textual center menu will appear to you with this items in it:

Try Ubuntu without installing
Install Ubuntu
Check disc for defects
Test memory
Boot from first hard disk

Please select "Test Memory" to deeply test your ram healty, if your pc freeze at installation or installation doesn't start.

Please select "Check disc for defects" and press enter to test if your cd-driver can read in a good way the live install cd... or if the install cd have some defective file in it.
Then please also perform a Test memory to be sure your pc RAM memory have not any issue

If you get a blank screen at boot after install or booting from the Ubuntu install cd please read:

http://www.ubuntugeek.com/how-to-fix-ubuntu-10-04-lts-lucid-blank-screen-at-startup.html

If you have trouble with intel8xxx graphic cards:

please try this: https://wiki.ubuntu.com/X/Bugs/Lucidi8xxFreezes

--- 7) Ubuntu Manual, it's very informative: http://ubuntu-manual.org/
Click on the "download Button" to download the latest PDF version.

The online help https://help.ubuntu.com/10.04/index.html

--- 8) Relax and fun
http://planet.ubuntu.com/ and Full Circle Magazine http://fullcirclemagazine.org/

If CD don't launch, errors can be:
  1) defective CD (see check MD5)
  2) defective hardware (e.g. lens not clean): try to boot another OS CD, e.g. Windows Repair
  3) BIOS order not properly set (hard disk before CD): try to boot another OS CD, e.g. Windows Repair

What's the status of your bug ?
If it is solved could you mark question solved.
Else I will have times in the following days to follow your issue.

Had several bad CD/DVDs....bought new packs and worked fine