Help with mpg songs.

I registered with Lime Wire and have download several songs. The only problem is I can only listen to them while I'm logged onto Lime Wire. What I want to do is burn a cd with them. Someone suggested I download i-tunes and import the downloads from Lime Wire ... then burn from i-tunes. So, I go to i-tunes and download for Windows XP. In the midst of downloading i-tunes I get the following message:

Quick Time can not open the destination file 'C:\WINDOWS\system32\Quick Time Authoring.qtx' The file may be in use by another application or marked read only. Close the application or change the file's read only attribute and try again

Somehow I managed to download i-tunes despite doing anything regarding the Quick Time message however when I tried to open i-tunes I received the following message:

Quick Time version 6.3 is installed. i-tunes requires Quick Time version 6.4 or later.

Soooo, I go to Quick Time download and try to download 6.5 but all I get is the message about Quick Time not being able to open the destination etc.

What gives?? Is there a better way to burn a cd from mpg files???