To recover System MBR from 100mb partition into Windows 7:
Boot Windows 7 DVD Repair Console or Repair CD
, Press SHift F10 at first screen, type in Command box:
SELECT DISK 0 (confirm this is Windows 7 HD)
SELECT PARTITION 1 (confirm this is 100mb Sys Reserved)
SELECT PARTITION 2 (confirm this is Windows 7 partition)
SELECT DISK 1 (confirm this is 2 tb data drive)
SELECT PARTITION 1 (confirm this is data partition)
Now enter DVD/CD Repair console, click through to Recovery Tools list to run Startup Repair up to 3 separate times with reboots
to write the MBR to Windows 7 partition until Windows 7 starts.
Now try saving a Windows 7 backup image to data drive.
Once you're sure you don't want 100mb any longer, you can use free Partition Wizard bootable CD
to delete 100mb partition and Resize Windows 7 into its space.