there is no iso file

and i'd like to say that my internet connection is too slow and it is hard to download again :-s

If you have a slow internet connection and you are currently on Windows, trying Wubi: www.wubi-installer.com
And your current issue is quite difficult to understand. You downloaded the iso file, but could not find it?

no.....i downloaded ubuntu from the site but i found it not in the iso form ....as before i downloaded the beta version and i found an iso file ...but this time i found the installer that started tha download again as if i didn't download 697 mega before ....!!!!!!!

What form is the download in? Something either went wrong in the download, or a misconception on your part. I strongly suggest Wubi.

it was in rar format .....then i extracted the file and found niether exe. nor iso ...plaese help me i know i am booring

heeeeeey please some body helps me ..these files i found after extraction :

 .disk folder
  casper folder
  dists folder
  install folder
  isolinux folder
  pics folder
  pool folder
  preseed folder
  autorun file
  md5sum file
  readme.diskdefine file
  ubunto file
  umenu file
   wubi file

You have downloaded something different. You will have to download it again from the link below, or use Wubi.
http://www.ubuntu.com/getubuntu/download

how come ?? something diffrent !!!......i downloaded from the official web site of ubuntu it is to easy for you to tell me download again ....i need one more month ...so i wait for a newer version of ubuntu may be 9.04

9.04 will be released in about one years time. Waiting is quite useless. You seemed to have downloaded from a completely different source, else a different file. There is no way you would have downloaded a .rar file if you did it correctly. If you do wish to keep working with Ubuntu, simply download from the link I gave you.

cloudfx......sorry..... you are quite useless

You are not explaining your issue. In fact, you do not seem to have an issue at all! You simply downloaded the improper file, and are now choosing to wait till 9.04 comes out to download that. If you do not wish for assistance, please do not waste people's time answering invalid questions.

does your failure and your low experience drive your mind to the idea that i don't have a problem at all !!!!! all these explanation about the problem you consider it kidding ....you wasted my time ..i wanna tell you that i faced this problem before and reinstalled ubuntu beta from other site and i do tried it..but i wanted the full version 8.04 .
but on other hand for this intolerant support services i realized that windows is the best ever ...may be you don't care because your system is free of charge ...

Thanks Urbán Dániel, that solved my question.