The biggest difference is the greatly improved security updates with XP. There are less glitches and breakdowns with XP. The following is from Microsoft’s website: Microsoft Windows 98, Windows 98 Second Edition (SE), Windows 95, and Windows NT Workstation do not include many of the security features of our latest operating system,

Windows XP with Service Pack 2. It is recommended that you should upgrade your operating system by acquiring Windows XP Professional or Windows XP Home Edition so that you can take advantage of the many security features. 

Benefits of upgrading to Windows XP with SP2 include: 

1. Windows Security Center: Enables you to manage your computer updates, your firewall, and even your antivirus software with a single view of important settings and tools. Also provides alerts when security settings are at risk. 

2. Windows Firewall: Helps in increasing computer security and reduce the risk of network and Internet-based attacks as soon as you start your computer. Turned on by default and built-in to your operating system. 

3. Automatic Updates: Helps you automatically stay up-to-date with the latest updates for your operating system. Also, includes new technology to make it easier for dial-up customers to download updates. 

4. Internet Explorer download monitoring: Warns you about potentially harmful downloads and gives you the option to block files that could be malicious. 

5. Internet Explorer Add-on Manager: Enhances security and reduces the potential for crashes by allowing you to manage Internet Explorer add-ons (programs that have been added to the Web browser). 

6. Internet Explorer Pop-up blocker: Makes browsing of the Internet more enjoyable by enabling you to reduce unwanted ads and content. 

7. Attachment Manager: Monitors and disables potentially unsafe e-mail attachments, which could contain viruses that might spread through Internet Explorer, Outlook Express, and Windows Messenger. 

8. Outlook Express privacy update: Helps reduce unwanted e-mail by limiting the possibility of your e-mail address being validated by potential spammers.