Not able to install dual-boot operating system…

Hi everyone….
I am currently using Windows 7& i want to have Linux operating system.So i planned
to install after installing the Windows 7.Then i installed Redhat 6 version correctly ,using grub loader i mentioned the other operating system..when i boot it loads grub it shows 2 operating system in list..when i try to boot the windows 7 ,Its booting showing ,boot manager missing…& i used the recovery cd cleared the error..but my linux is not running……how i should boot ?

myself having 2ghz core2duo processor & 4GB ram tooo……help me pls…