Curently I have MDK82 and I wanted to upgrade it. When I put CD 1 to cdrom
installation doesn't begin,despite that I have choosed in BIOS to start
booting from cd. So I created a start floppy .When I choose in Lilo to boot
from floppy I got mesagge :" Boot failed" . What now?
Format Linux partition and remove Lilo?

Did you change your bios setting back to floppy as first boot device? Was there a floppy in the drive when you made your selection? In what environment did you create the start floppy?

I have created floppy in Windows using rawwrite.exe which is
on CD1 install disc. I haven't changed BIOs settings.

Change your bios settings to reflect booting from floppy, then your floppy will boot.
Make a boot floppy with Windows
If your computer cannot boot from the CDROM and previous methods do not work, you must make a boot floppy under Windows as follows:
Insert the CDROM, then open the icon "My Computer", right click on the CDROM drive icon and select "Open"
go into the "dosutils" directory and double-click on the "rawwritewin" icon
insert a blank floppy in the floppy drive
select "D:\images\cdrom.img" in the "Image File" field (assuming that your CDROM drive is "D:", otherwise replace "D:" as needed)
select "A:" in the "Floppy Drive" field then click on "Write".
To begin the installation:


insert the CDROM in the drive, as well as the boot floppy, then
restart the computer.