try going into safe mode. press and hold the F8 key as the computer starts to poweron. if it shows you a screen for selecting a boot device, select the hard drive, and then quickly press and hold on the F8 key again.

if pressing the F8 key works and brings you to safe mode, then we know that the basic windows core of the computer is still intact. some program that runs on systerm startup must be the one causing the boot problems. see if you can uninstall unwanted programs while in safe mode.

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usually, clearing the CMOS does not affect the operating system. one obvious effect though is that the system clock on the motherboard is reset -- and so the windows clock is also reset. after resetting the cmos, i suggest you configure the settings and make the correct time and date.

ALSO,
just a curious thought. check again that your cmos settings have detected the hard drive, cdrom and whatever peripherals are connected to your computer. its slightly possible that after clearing the cmos, the computer has not detected which hard drive to boot. you might have to set it back again in the cmos settings.

goodluck on this