People say that Windows 2000 has reached its end of support period. Bug fixes/security patches will not be issued even if there are. So, for this reason, I think we shouldn't use Windows 2000 at corporate/enterprise environments. Do you agree or not?
There's no 'people say that' here; It has reached its end of life. This is clearly documented on the Microsoft website.
If I had windows 2000 deployed and it was still doing everything the business needed then I'd want to upgrade, but if its a big deployment and funding an upgrade is a problem then you have to be realistic. I'd also say that being realistic goes both ways, the business would need to understand that new server hardware will very likely not support Windows 2000, that security will be an issue where patches are not produced, and the 'latest and greatest' applications from both Microsoft and third parties are going to expect to be working with a newer version of Windows / AD.
There's no way in hell I'd start a new deployment with anything less than the latest OS, for the reasons mentioned above.
Bug fixes and patches is not the only reason to remove Win2k systems from production.
Efficient Admins will create new tools using the most practical method. Most of these new methods are not available on the old server, therefore you have to either support two lines of tools, or manage the new servers with outdated tools - both situations cost a lot of time.
Let´s look at Powershell: It can be made to somewhat work, but not fully. For instance, the wonderful set-owner tool doesnt work on win2k.
Having to haul around a Win2k Server is a burden. Migrate it.