do i need to reinstall installed files from synaptic package manager after i notice misbehaviour of my computer ?

ok the best option is boot into recovery mode and then choose the third option ie fix broken packages, let it update and upgrade the system and then reboot...other thing to note is check whether you are running deluge or any other download manager side by side that could pose problem, i was facing such problem so stopped using bittorrent programs for downloading but this is not the issue with normal downloads.
that should fix your problem.
regards
Rajinder

hi Rajinder,
 thanks for reply.
I don't use bit torrent for downloads, i never tried it ever since.
I am sorry but i do not know how to boot by recovery mode , i am new in linux..
will you tell me how ?
 thanks a lot !

that is when you switch on the laptop....you are given option to ubuntu 9.10 Generic then ubuntu 9.10 Generic (recovery Mode) and windows 7
 select the second one and then hit enter....
when laptop boots and reaches to its last level you will be presented with a window.
having 6-7 entries in that select repair broken packages (entry no. 3) it will update and upgrade and fix broken packages....after it is over then again you will be in the same window...then choose the last option go to root shell after you reach in root shell type reboot it will reboot the laptop then only whole process is over.
regards
Rajinder

hi,
when laptop turns ON. i only see the word UBUNTU , then the log-in name and
password box, at he bottom panel i see"language","keyboard","session". when
i click session , the options are " failsafe gnome, xterm,gnome.
is the option failsafe the same as safe mode in windows 7, and the recovery
mode of linux the same as system recovery on windows OS,, that is how i
understand the difference.. i am not sure.. sorry..

i again went to synaptic pckg mgr.. then reinstall some installed files,,
laptop now for the mean time behaves well.. not sure . i don't use some
application installed..
also, on synaptic mgr. i saw edit then an option to fix broken packages.. i
click it then after awhile at the bottom of the of the window it says,,
"successfully fixed broken packages"..
i am still observing the behaviour,, i just opened laptop now ...i will try
some applications too..
ok thanks so much Rajinder !

On Wed, Apr 7, 2010 at 3:30 PM, Rajinder Sandhu <
<email address hidden>> wrote:

> Your question #106614 on Ubuntu changed:
> https://answers.launchpad.net/ubuntu/+question/106614
>
> Rajinder Sandhu proposed the following answer:
> that is when you switch on the laptop....you are given option to ubuntu
> 9.10 Generic then ubuntu 9.10 Generic (recovery Mode) and windows 7
> select the second one and then hit enter....
> when laptop boots and reaches to its last level you will be presented with
> a window.
> having 6-7 entries in that select repair broken packages (entry no. 3) it
> will update and upgrade and fix broken packages....after it is over then
> again you will be in the same window...then choose the last option go to
> root shell after you reach in root shell type reboot it will reboot the
> laptop then only whole process is over.
> regards
> Rajinder
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/ubuntu/+question/106614/+confirm?answer_id=2
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/ubuntu/+question/106614
>
> You received this question notification because you are a direct
> subscriber of the question.
>

hi,
 yes so far it is stable now, even the letters on the screen are in focus/clear..
i did not reinstall all the packages installed, but only the packages which i am familiar.
i will still observe while i surf internet, it is fast again.. i am happy..
thanks so much!