Building upon the focus areas you've highlighted, let's delve deeper into the setup of Active Directory (AD) on Server 1, including the DNS and DHCP roles for IP Address Management (IPAM), and the setup and management of a RADIUS server for Authentication, Authorization, and Accounting (AAA) capabilities on Server 2, within a Windows 2000 Server environment. This refined guide will extend the foundational steps with additional depth, including considerations for secure and effective configuration and management.

### Deep Dive into AD, DNS, and DHCP Setup on Server 1

#### Operating System and Roles
- **Operating System:** Windows 2000 Server.
- **Roles:** Active Directory, DNS, and DHCP for comprehensive domain management and IPAM.

#### Enhanced Configuration Steps
1. **Active Directory Setup:**
   - **Pre-Installation Checks:** Ensure the server meets the hardware requirements. Verify network settings and server's static IP address.
   - **Running `dcpromo.exe`:** This not only installs AD but also prompts for DNS installation if not already present. Choose to install DNS during this process for seamless integration.
   - **Domain Naming:** Select a meaningful domain name that reflects your lab's purpose or organizational structure.

2. **DNS Configuration:**
   - **Forward and Reverse Lookup Zones:** Essential for resolving hostnames to IP addresses and vice versa within your network. Consider integrating with DHCP for dynamic updates.
   - **DNS Forwarders:** Configure forwarders for efficient internet access, directing queries for external domains to your ISP’s DNS servers or other known reliable servers.

3. **DHCP for IPAM:**
   - **Scope Definition:** Tailor DHCP scopes closely to your network layout, including subnetting details if applicable. Allocate ranges that accommodate all client machines while reserving addresses for static assignments.
   - **Reservations and Exclusions:** Use reservations for devices requiring consistent IP addresses but managed through DHCP. Exclude addresses that are statically assigned to servers and network infrastructure.

#### Account Management Best Practices
- **Group Policy for Passwords:** Utilize Group Policy Objects (GPOs) to enforce password complexity, history, and length requirements across all user accounts.
- **Administrative Accounts:** Create role-specific administrative accounts (e.g., DNSAdmin, DHCPAdmin) for task delegation, minimizing the use of high-level accounts for routine tasks.
- **Audit and Review:** Implement a schedule for reviewing user account permissions, ensuring adherence to the principle of least privilege. Employ auditing tools or scripts to assist in this process.

### Comprehensive Setup and Management of RADIUS Server on Server 2

#### Operating System and Role
- **Operating System:** Windows 2000 Server with Internet Authentication Service (IAS) for RADIUS functionality.
- **Role:** RADIUS Server to provide AAA services for network access and management.

#### Detailed Configuration Steps
1. **IAS Installation:**
   - **Component Addition:** Through the Windows Components wizard, add IAS, which provides the RADIUS server functionality.
   - **Active Directory Registration:** Registering IAS in AD is crucial for leveraging AD's user and computer accounts for authentication and authorization.

2. **RADIUS Client Configuration:**
   - **NAS Registration:** Identify and register each network access server (NAS) as a RADIUS client within IAS. Careful naming and description help in managing multiple clients.
   - **Shared Secrets Management:** Establish a protocol for creating, storing, and periodically changing shared secrets. Consider a password manager or secured document for tracking.

3. **Policy and Logging Enhancements:**
   - **Conditional Access Policies:** Go beyond basic policies by implementing conditions based on user groups, time-of-day restrictions, and service types (e.g., Wi-Fi, VPN).
   - **Comprehensive Logging:** Configure IAS logging to capture detailed information for auditing and troubleshooting. Consider centralized logging solutions for ease of analysis.

#### AAA Configuration Best Practices
- **Security of Shared Secrets:** Employ mechanisms to ensure the confidentiality and integrity of shared secrets, both in storage and transmission.
- **Regular Policy Review:** Periodically review RADIUS policies to ensure they align with current security policies, user needs, and network configurations.
- **Logging and Monitoring:** Establish monitoring routines for RADIUS logs to quickly identify and respond to authentication issues, security threats, or policy violations.

### Conclusion
By following these detailed steps and best practices for setting up AD, DNS, DHCP, and RADIUS services on Windows 2000 Servers, you'll create a robust, secure, and functional network infrastructure. This infrastructure not only supports comprehensive IPAM and AAA capabilities but also adheres to best practices for system and user account management, ensuring a secure and efficiently managed network environment.