Nokoon,
Please follow these steps for assistance:
Step 1 is to download and run the utility at this link http://go.microsoft.com/fwlink/?linkid=52012, then click the Windows tab, Copy to Clipboard, then paste the report into a new message in this section of the forum: http://forums.microsoft.com/Genuine/ShowForum.aspx?ForumID=442&SiteID=25.
Step 2 is to look on the computer or with the materials you received with the computer or with Windows to see if you have a Certificate of Authenticty (COA). If you have one, tell us about the COA. Tell us:
1. What edition of Windows XP is it for, Home, Pro, or Media Center?
2. Does it read "OEM Software" or "OEM Product" in black lettering?
3. Or, does it have the computer manufacturer's name in black lettering?
4. DO NOT post the Product Key.
Not sure what to look for? See this page for reference: http://www.microsoft.com/resources/howtotell/en/coa.mspx
In hindsight, you would have been better off not doing anything so quickly and coming to this forum to test the waters. Assuming that the installation of Media Center was the original out-of-the-box from Compaq, it's likely your problem would have been cleared up in a couple of postings with MS tech reps here on the forum.
Doing two system restores and then an attempt to do an OS recovery no doubt has left your installation of XP in a shambles! I am just wondering why the on-disk OS recovery did not work for you.....