very slow

Ubuntu is very heavy, many other versions of linux are much lighter on system resources. Please let us know your cpu speed, ram size and how much hard-drive space you gave to ubuntu. Also please let us know whether you have just 1 option for booting into Ubuntu and 1 for Windows or do you have a lot of different options for booting into Ubuntu?
Good luck and regards from
Tom :)

well asus P5B-mx motherboard, 1gb ram,intel core2duo 2ghz ,160gb hard disk, two operating system ubuntu(9.04) and xp(sp2)
made partion of 10gb for ubuntu

Lol, that's really quite high spec. Ubuntu feels a lot more comfortable with 15Gb rather than just 10Gb but that shouldn't be causing problems such as you describe. If you could easily reinstall 9.04 then maybe it might help - i found i had to reinstall linux quite a few times before i realised what i had been doing wrong on my machine. you'r looks nicely set up though so it's difficult to see anything that might be causing a problem.

Have you gone up to the top taskbar and clicked on

System - Administration - Computer Janitor

That can usually clear up quirky behaviour such as you are getting. Also please open a command-line
https://help.ubuntu.com/community/UsingTheTerminal#Starting%20a%20Terminal
and type in

free -m

and give the output in here. This will show us the amount of ram and swap-space which are the 2 normal issues when dealing with slowdowns. Also sometime when you next boot-up please try the "memtest" option. It does take quite a long time but should show if there are odd problems with your ram. it would make a lot more sense if you had installed Ubuntu onto a virtual machine inside Windows because Windows takes up a lot of ram space which might not leave enough for ubuntu but i think you have installed as a normal dual-boot so again it's a bit baffling why you are getting this problem.

Ok, so things to try; a memtest from the boot-menu. From the command-line copy the output of

free -m

into here. Also try "Computer Janitor" from the top taskbar & please then tell us how all that went.
Good luck and regards from
Tom :)

hi tom
thanks for reply
 ya when i next boot up the system i will go for memtst option

prasanna@prasanna-desktop:~$ free -m
             total used free shared buffers cached
Mem: 994 547 447 0 47 237
-/+ buffers/cache: 262 731
Swap: 0 0 0

Lol, i think i might have spotted one thing that might be causing things to be slow. I think we need to make a linux-swap partition of about 2gb, or perhaps a little less if you don't have enough free-space on your hard drive
https://help.ubuntu.com/community/SwapFaq

Note that it is much better to have a separate partition for swap, preferably on a different drive from your main Ubuntu OS partition. Using a swap-file as described at the end of that guide is a really bad plan. It's one of the reasons Windows suffers from slowdowns so badly although linux would be affected quite that badly, but it's still a bad plan. A separate partition is a much better plan.

Ok, please boot-up a LiveCd session
https://help.ubuntu.com/community/LiveCD
and in that guide scroll down to look at figure 3 to help open the Partition Editor and then copy the info from the bottom half of that into here so we can help tailor your system to be much faster.

Good luck and regards from
Tom :)

In the Swap Faq it's particularly the sub-subsection

"Swap can optimize memory usage:
    * Hard drives are considerably slower than RAM. So, when you need a file (be it a data file like a video, executables like Firefox, or libraries), the Linux kernel reads the file into RAM and keeps it there, so that the next time you need it, it's already in RAM and data access is much faster (thousands of times faster). The portions of RAM that accelerate disk read are called "cached memory." They make a huge difference in terms of responsiveness.
    * The Linux kernel automatically moves RAM reserved by programs--but not really used--into swap, so that it can serve the better purpose of extending cached memory. "

As you see the Ram is getting cluttered with stuff it would normally quickly stuff into Swap to maybe access later if required. It's this juggling act between Swap and Ram that helps an Operating System run a lot faster. Just as a juggelr can keep more things up in the air than he/she could hold in their hands at any one time ;)

Windows calls their swap-file "pagefile.sys" and they make it able to keep changing size and jump around the drive a bit so ram is never sure of exactly where anything is. Also because it's Windows pagefile.sys suffers badly from getting fragmented and Windows defragmenters can't usually defragment system files! Lol! Linux avoids all these problems quite neatly by allowing us to have separate partition for swap that ram can easily find and use.

I hope this helps!
Good luck and regards from
Tom :)

Hi :)

Have you been able to try the new Ubuntu 10.04 before it gets officially released?
http://www.ubuntulinux.org/testing/lucid/beta2
Trying it as a LiveCd or as an extra dual/multi-boot would be ideal. Developers and everyone are keen to try to iron out any problems before 10.04 gets officially released so you might find faster & more effective answers to your bug reports which would make 10.04 work better on your system for you

Thanks and regards from
Tom :)