I downloaded Knoppix 17-5-2004 version.After burning successfully and booting from CD, it started Live CD then it said,
Looking for CDROM in: /dev/scd0 then scanned something and said,
Can't find KNOPPIX filesystem, Sorry Dropping you to a (very limited) shell.
Press reset button to quit.
Please help me why is this happening? !

Knoppix does not like some of the hardware ( just what do you have in the system BTW ) in your system or is getting the settings wrong. You are going to have to use some cheat codes to get you system going the first I would suggest using is knoppix failsafe to boot with minimal hardware detection to confirm that it will work with your system then if it does then you will have to try using some of the no??? cheat codes. You would type in the failsafe cheat code I mentioned at the opening screen and hit the ENTER key and knoppix will boot using the failsafe method you can put many cheat codes on one line eg knoppix xvrefresh=60 noddc vga=normal and it uses those sections of code or skips it in the case of a no?? cheat code. BTW there is a knoppix forum you may want to check out to see if anyone has similar problem with your type of hardware located at http://www.knoppix.net/forum/.

Well I downloaded Karen's Hasher.For the Knoppix.iso when I computed I got the hash as 7EE0382655ABF194AA300A98100CACDE
Then Should I also have to compute the hash for that .md5 file or just compare that value with that .iso hash value?
When I opened that .md5 with notepad the value was,
7ee0382655abf194aa300a98100cacde *KNOPPIX_V3.4-2004-05-17-EN.iso
But when I pasted this value into that text window and clicked on compute tha value was DC45CECCB080323CB0CB0B6455A4FB4A
And status for both was OK. So anything wrong?

I do not know what you are trying to do with the second value but for the first it is correct for the md5sum for the iso so it looks like it was a good burn. So did you try my suggestions?