Dual Booted 7 and Xp Errors help

Hello I have a Windows 7 Toshiba satellite a505 s6980. I Dual booted it with Windows xp professional. I never used to have any problems but now all of a sudden I think I messed up something by accident. Because even after fresh clean reinstall. The computer doesn't boot to any os. I boots to a screen that says bootmgr missing or something please restart. I have 3 partitions. 1. C: System Reserved 100 gigs. 2. D: Windows 7 348 gigs. 3. F: Windows do 97 gigs. How can I make it so that Windows 7 my main is and I can properly dual boot between Windows 7 and Xp. Each time I add co back to the boot menu with easybcd while in Windows 7. Sometimes it restarts and I get the boot menu is selection, and I get to log into co. Sometimes the co selection gives me missing Khmer error, and when ever I shut down or restart the computer the os selection disappears and It boots to no is and I get the checking hardware and missing bootmgr please restart. Please help me fix everything to the proper working xp and 7 dual boot again. I have no Windows 7 dvd, just a repair disk