Converting Japanese to English in laptop

my frontier mini-laptop is configured in japanese language, how can i change it back to english

Does it have a Japanese keyboard? If so, you switch between Japanese input and English (alphanumerical) input by pressing "Alt" and the key that says 漢字 - usually near the "Esc" key, maybe there is a key that says "半角/全角　漢字"?
Is this what you mean?

Unless the windows have different language select preinstalled in the control panel (windows 7), or windows 8 in similar settings, which you just to alter the setting, without English which many Japanese PC might not have, you will have to download the language pack which will depend on which version of windows you have, you can check this out online through windows update.

Other options is to install a fresh copy of a English version windows or use a language conversion program(can't remember what it's call, I have in on my PC, but it's has a dead ram so I cannot check this out ATM.

If you are just referring to the keyboard, you can just buy a keyboard panel as a spare part from the manufacture, but will cost a lot.