No, Windows Defender is not available on Windows XP. However, there are some other affordable security options available for Windows XP users. I would recommend checking out Affordabekey. which is a best-selling website for all kinds of security solutions. Right now they have a Month Ends Super Sales offer with up to 70% discount, if you use the coupon code XMAS22.
You can use Windows Defender to disable programs that run at startup, or using System Configuration.
Yes Windows Mail is available for Windows XP as part of Windows Live.
No, but you can get Windows Live Mail for Windows XP in Windows Live Essentials for XP.
Windows XP with SP2 and SP3
The Qt widget toolkit is not installed by default in Windows XP. Windows applications can use the Qt toolkit in Windows XP, and the QT SDK is available for Windows XP.
There 3 versions which are windows professoinal,home professional and media centre.
Windows Media Center isn't part of Windows XP Professional. It was only available in Windows XP Media Center Edition.
In Windows XP, where would you go to view the computer's available resources
A Defender? I am going to assume you mean, Windows Defender. Its is a program that helps (doesn't do a great job) prevent malicious software from ruining your computer. Full details are here: http://www.microsoft.com/windows/products/winfamily/defender/default.mspx
Windows XP service packs 2 and 3. AGN
The reason could possibly be that Windows Vista was an upgrade, and had an upgraded firewall. Windows Vista also had Windows Defender installed by default, however, XP required a download for it. Windows Vista also patched several common exploits in Windows XP which were being used in viruses.