For what purpose you installed that tool?
Actually this tool use to p2v (Physical to virtual),v2v (Virtual to virtual) means you can virtualized your machine to virtual machines(vmware infrastucture). That is the reason its asking for an virtual infrastructure server where the machine will be hosted after conversion.
Standalone is the naming convention and there are below differences between vcenter converstandalone and enterprise version. Just for your knowledge..
VCenter Converter Standalone is an application that installs on Windows machines. Enterprise is integrated into te vSphere client and is available as a plug-in to vCenter Server. The main differences between the two are the following:
- Standalone supports Windows and Linux conversions; Enterprise only supports Windows.
- Standalone supports ESX, ESXi, vCenter Server, Workstation or Fusion as destinations; Enterprise only supports ESX, ESXi and vCenter Server as destinations.
- Standalone supports hot-clone conversions; Enterprise supports both hot-clone and cold-clone conversions.
- Standalone supports one-time conversions; Enterprise supports scheduled and recurring conversions.