Boot sector for system disk partition is corrupt

hi guys! I am now able to see my partitions after following the steps here Partition Wizard Bootable CD allows user to manage partition directly with partition manager bootable CD.. It shows my old partitions now, but when I rebooted my computer and tried to boot from HD, it still says "Reboot and select proper boot device". Is there something else that I need to do or click on the Partition Wizard menu? I'm sorry, but I do not know how to use this step-by-step. I'm afraid to click on either of those menus as it might cause more damage than fix it if I choose the wrong option. The only other thing I've clicked was the option that says "Rebuild MBR" and it says "Successful" after clicking on the "Apply" button.

The link you posted to PW boot disk does not show us how you recovered your failed partition.

Did you run PW Partition Recovery Wizard and complete the steps to recover any partitions it discovered, as shown in the video? If not, do that now.

Once you do this, confirm Win7 or it's 100mb System Rserved partition (preferred) is marked Active, then click on the HD to highlight it, from Disk tab select Rebuild MBR and apply both steps.
How to Set Active/Inactive partition -Partition Wizard Video Help.
Partition Wizard Rebuild MBR Video Help.

Make sure Win7 HD is set first to boot in BIOS setup.

Reboot to see if WIn7 will start. If not boot into the Win7 DVD or System Repair Disk
to run Startup Repair - Run up to 3 Separate Times. Trigger the disk to boot by tapping vigorously from the point you power up the PC the Asus F8 BIOS boot menu key given on first screen.

thank you gregrocker! I will now try to do the steps as you've mentioned. I really appreciate all your replies and keeping up with me :)

It would be good to know what you've done. Can you answer my questions first?

oh, sorry! When the main window of Partition Wizard launched, I simply clicked on "Partition Recovery Wizard" under the "Wizard" tab. I clicked on "Quick Scan" and it found three partitions: System Reserve, drive C and my Drive D. I checked on each one of those, then clicked on "Next" button then "Apply".

And this recovered the partitions to where they were before, and you have the System partition still marked Active?

gregrocker said:

And this recovered the partitions to where they were before, and you have the System partition still marked Active?

After the partitions have been discovered, they are all marked "None" instead of "Active".
I am now following the steps here How to Set Active/Inactive partition with partition magic? Partition Wizard Video Help.

I have followed your instructions up to setting my HD as the 1st boot priority in BIOS. I am now getting "BOOTMGR is missing. Press CTRL+ALT+DEL to restart." I will now try to do the steps here: Repair CD - System Repair Disk and here: Startup Repair - Run 3 Separate Times

Which partition did you mark Active?