Calculator not present in the start menu.

Resolution:

Start >> Control Panel  >> Add or Remove Programs  >> Add/Remove Windows components

Accesories and Utilities >> details | Accesories >> details | Uncheck calculator >> OK >> Next

Control Panel  >> Add or Remove Programs  >> Add/Remove Windows components

Accesories and Utilities >> details | Accesories >> details | put a check on calculator >> OK >> Next (XP CD would be needed)