Make sure you have a password (make one if not - SystemPreferences:Users&Groups).
Launch Terminal from Applications:Utilities
Close all Finder windows.
At the UNIX shell prompt enter the following UNIX command:
sudo find /-name ".DS_Store" -depth -exec rm {} \;
When prompted for a password enter the Mac OS X Administrator password.
This command is to find and remove all occurrences of .DS_Store starting from the root (/) of the file system through the entire machine.
If the problem still remains with particular window, you will need to copy any DS_Store file in that directory manually.
Enter the following UNIX command:
defaults write com.apple.finder AppleShowAllFiles -bool true
Then:
killall Finder
Open Finder window and copy DS_Store file. Then paste it to the directory which had previously displayed is not correct.
Enter the following UNIX command:
defaults write com.apple.finder AppleShowAllFiles -bool false
Then:
killall Finder
So this way I fixed the bug with displaying the size of windows on my computer (Mac OS X 10.7.2).