Removing snapshots from VMs is really quite straightforward.
The following will remove all snapshost from all VMs.
Get-VM | Get-Snapshot | Remove-Snapshot -Confirm:$false
If that is not what you want, you will have to give more information on how to select the snapshot(s) to remove.
For using the Windows Task Scheduler, have a look at Alan's Running a PowerCLI Scheduled task post.
