You will have to provide more info, to what you did not understand - because its not helpful or productive to say "you do not understand"
. 90% of my prior reply was addressing your TFTP folder set-up question, and 10% on the DHCP.
So you did not understand the folder information provided on TFTP? If not please explain.
As for the DHCP set-up info provided prior, that is my network IP addressing, and was not intended for you to use.
So if the dhcp range is 192.168.1.101-192.168.1.199 can i use 192.168.1.51 and 192.168.1.52 (ip's are free)
No, that would not work. If your scope is set how you say, it would only hand out IPs starting 101 thru 199. Not .51 or .52
You would need to change your DHCP config range to match the free IPs (.51 and .52), and make sure you also change your max_leases 2 - otherwise it will have an error. Like I said prior, start small, and when its working, then expand.
start 192.168.1.51
end 192.168.1.52
interface eth0
max_leases 2
After saving your congfig, and if your terminal server is running, kill it, and start it again. Then power up 1 client computer, and see if it gets "192.168.1.51"
When my box gets an ip - here is a log of it.
tc@BOX-165:~$ sudo udhcpd -f /netboot/udhcpd.conf
udhcpd (v1.22.1) started
udhcpd: can't open '/var/lib/misc/udhcpd.leases': No such file or directory
Sending OFFER of 192.100.99.99
Sending ACK to 192.100.99.99
As for the .0 file - its a PXE bootstrap file (nbp network bootstrap program). You will need something like this, before you can load the ISO or as gerald_clark suggested - load "kernel and core.gz", which is what I normally use.
If you need the .0 bootstrap file - check out "syslinux.org". Or search for IPXE - but that might be too advance for you to use initially, but it might still help to review it. I know IPXE can be set-up to load ISO.