I am very confused about this folder. I really want to know that if I reinstall my windows again will the second windows.old folder make it lagier or change anything. Can I delete the windows.old folder or do I need it.
Windows.old is essentially your old "program files" if you don't need anything from the previous installation of windows (before you upgraded) feel free to delete it and save space. It won't harm the computer, but it may contain data you have forgotten about or need, check it out first, delete it otherwise! Save that hard-drive space!
does anyone know were you found all the drivers in the windows.old like AUdio and sound so I didnt delete it.
Drivers are associated with the current operating system, you will probably need to find compatible versions for the new install. I'm not sure if I'm answering your question but you don't really need those drivers from the previous installation, and if you end up needing one of them, you are better off getting new, compatible ones.
The short answer is No. You don't really need the Windows.old folder. If you re-install Windows again (assuming you won't format your harddisk), you will get another file called Windows001.old instead of Windows.old.
If you had like to roll back to the previous Windows version, you might want to use the Windows.old folder. Here's a guide how you can do that: http://support.microsoft.com/kb/971760