1. First from edit setting of VM, do you see disk pointing to snapshots or just vm.vmdk. If snapshot, it will show vm-00001.vmdk.
2. if running on snapshot, check size of snapshot from datastore, if very small, you can just remove and base disk.
3. From edit settings of VM, if it is running on snapshot, it will not allow you to edit the size of VM - just note
4. what is error that you see when trying to power on VMs