Why is my browser underlining everything red?

My little sister messed something up on my computer a couple days ago but I don't know what. Every time I turn my computer on, it says java.exe or something is corrupt or erased and it My OpenOffice word program won't open because it has been "terminated." Now when I type in any box on any website, especially Yahoo! Answers, every single word is underlined red as if I misspelled it. How do I fix it? ): I need to do my homework on OpenOffice and my computer is corrupt!