Use Ctrl-Alt-Del To Login

The generic way to login to Windows XP is through the Welcome screen:

If you would prefer to login by pressing Ctrl-Alt-Del instead of using the Welcome screen:

This guide can help to you:

1) Click the Start Button
2) Click the Run Command
3) In the Run Command Windows type "regedt32"
4) Navigate to each of the following areas and change the value as listed:

[HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Winlogon]

Create a new DWORD value for "DisableCAD" with a value of "Zero"

Set The Value For "LogonType" to "One"

5) Restart the computer
6) Now the All Programs should be back in the Start Menu

Recommended Tools:
-Try this custom tool to automatically fix your problem: