Task Manager can be a pretty good ALT+TAB replacement.
To use Task Manager in the ALT+TAB replacement mode, you want to select the Applications tab, or remove all the other tabs.
The next time you need to ALT+TAB:
Press CTRL+SHIFT+ESC to open Task Manager. If the Applications tab is not selected, select it.
Use the DOWN ARROW key to navigate to the well described applications and press Enter to switch to it.
If your application starts with a J, you can press J to skip to the next J. Pressing J again will skip to the next J, and so on.
If you got to far, use the UP ARROW key.
NOTE: See the taskswitch.exe PowerToy for XP, which not only displays the icons of the application window, but lets you see a preview of the page which helps when you have multiple sessions of an application open.