Problem with accent and other symbols in Windows XP

sminfo--Click IE View|Encoding|More.  Is the checkmark next to Cyrillic?  If not what Encoding is checked?  I get the feeling you are not located in the USA so do not know what Encoding should be default.   You could try AutoSelect and let the page decide.

In Control Panel start Regional and Language settings (you have to run it as administrator) and check out Advanced language settings for non-Unicode programs - it should match your language. If you need to change this setting - tick the box Make changes to current user and to Default User.  In case if you normally working under the account that is not having administrative rights on the computer then temporarily add this account to the administrators group, make change, reboot computer then remove the account from Administrators.
 

The problem is not only in IE. For example if I receive an email with Microsoft Oulook 2003 and the sender name have accent characters or something like that I receive it with 'special' character ...

I try changing the Regional Option settings for for non-Unicode programs, but the problem continues ...

I try too changing  the  View|Encoding option in IE checking and unchecking Auto-Select, selecting Western European (Windows), Unicode (UTF-8) and nothing happends ...

Could you be a bit more specific? I mean, by saying what your settings are.

What you have set in Regional and Language Options in Control Panel? Please note that the changes in this settings require reboot.

Also, have you checked in Internet Explorer | Internet Options | Languages | Language Preferences? What are your settings?

IE language:  English (United States) [en-us]

Regional and Language Option:  English (United States) (In every Tab and every option of this configuration)

What is the setting in in Internet Explorer | Internet Options | Fonts?

Web page font Times New Roman
Plain text font Courier New
And in Language Script is selected Cyrillic ...but anytime I change to Latin based when I enter a new IE seesion it's not keeped (continues with Cyrillic)...

I found some hits here: http://www3.ntu.edu.sg/home5/PG03053527/Tips/TipsForIE/Tip_for_IE.htm (the solution the article mention seems not be working in XP / IE7 - the registry settings must been change since that).

I think you are actually having a problem with Regional Settings (Advanced)  - the code page conversion tables are not set properly or somehow corrupted.

What I would advised to try is to change Non-Unicode program language to English (United Kingdom) and when prompted to use the installed fonts, answer No so the codes would been (re)loaded from Windows Installation CD. Reboot computer then change it back to your previous settings (English - US) and again answer No when prompted to use the installed fonts.

sminfo--From IE Help
"To override website font and color settings
If you want to have the fonts and colors you specify in Internet Explorer to be used for all websites, regardless of the fonts that have been set by the website designer, follow these steps.
In Internet Explorer, click the Tools button, and then click Internet Options.
On the General tab, click Accessibility.
Select the Ignore colors specified on webpages, Ignore font styles specified on webpages, and Ignore font sizes specified on webpages check boxes, and then click OK twice.


Changing webpage fonts and background colors
When web authors and designers create webpages, they often specify particular typefaces, fonts, colors, sizes, and background colors. These settings are specified for each item or they are set in a style sheet, which is a type of template for specifying how different styles should appear throughout a webpage or site.
You can override any or all of these settings."
If this problem started only recently you could try a System Restore.

P.S.  In one of your posts above you said "I try too changing  the  View|Encoding option in IE checking and unchecking Auto-Select"  I had suggested you check AutoSelect if it was not checked.  Does that mean AutoSelect was checked while you had the problem originally?

I try a System Restore at first time but it doesn't repair anything ...

At this moment I have checked AutoSelect ...

Congratulations!