Comment supprimer dual-boot

Bonjour a tous!

je voudrais installer Windows 7 64bits en co-habitation avec vista.
Mais le probléme c'est que j'ai deja un unbutu qui ne me sert a rien il est en mulit-boot donc je voudrais savoir comment supprimer unbutu afin de pouvoir mettre Win 7 par la suite!

Merci

Le boot resemble a sa :
[URL=https://imageshack.com/][IMG]http://img263.imageshack.us/img263/5505/photo0015zy.jpg[/IMG][/URL]

Uploaded with [URL=https://imageshack.com/]ImageShack.us[/URL]

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et on peux appuye sur "e" pour modifier les commandes c'est peux-etre la dedans :
[URL=https://imageshack.com/][IMG]http://img828.imageshack.us/img828/5240/photo0013w.jpg[/IMG][/URL]

Uploaded with [URL=https://imageshack.com/]ImageShack.us[/URL]

Uploaded with [url=https://imageshack.com/]ImageShack.us[/url]

sinon on peux aller dans panneau de configuration>systéme>avancé>démaragge et récuperation et sa donne sa :
[URL=https://imageshack.com/][IMG]http://img251.imageshack.us/img251/150/screendb.png[/IMG][/URL]

Uploaded with [URL=https://imageshack.com/]ImageShack.us[/URL]
Uploaded with [URL=https://imageshack.com/]ImageShack.us[/URL]