This is what you will see when you boot from the ISO.
Searching for "Windows Server 2003 R2 ISO" today leads you down a murky path. Official Microsoft distribution ended years ago. While you might find .iso files on abandoned FTP mirrors or archive.org, here is the critical warning: server 2003 r2 iso
Once the server boots to the desktop, the process is not quite finished. This is what you will see when you boot from the ISO
That means it has been over a decade since any security patches were released. you enter the graphical installation phase.
After the reboot, you enter the graphical installation phase.