That pesky 100MB partition is known as "system reserved" partition, a new "feature" introduced in Windows 7, it has nothing to do with recovery, which is always imposed by the manufacturer as a backup of their bloatware.
The system reserved partition exists just to support bitlocker feature, it serves no other purpose as far as I know, so for 99% of use cases, it's absolute unnecessary. Nevertheless Windows always creates it. There are a few tutorials instructing how to remove it on an existing system: System Reserved Partition - Delete
When clean installing, it's recommended to pre-format the HD so that it doesn't gets created in the first place, unless you plan to use bitlocker.