Hello,
You may want to try this:
To uninstall the all language packs, try doing this via Control Panel,
Regional and Language Options "install or uninstall display languages"
Choose the uninstall button and check the boxes of the language packs you
wish to remove.
English, German, French, Spanish and Japanese should not need to be removed
for the Service Pack to be installed.

Thanks,
Darrell Gorter[MSFT]

This posting is provided "AS IS" with no warranties, and confers no rights
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|> Thread-Topic: Cannot install Vista SP1 - Romanian language pack won't
uninst
|> thread-index: AciAVCMR0IucvgD9Qq2E57CVnDYtkg==
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|> From: =?Utf-8?B?VGltQWxzb3A=?= <TimAlsop@discussions.microsoft.com>
|> References: <123340BC-E58C-4951-87AE-60BA9B73AF73@microsoft.com>
<ACE8051C-6D27-4E78-A26B-197D6DEDDEA2@microsoft.com>
|> Subject: RE: Cannot install Vista SP1 - Romanian language pack won't
uninst
|> Date: Fri, 7 Mar 2008 05:07:03 -0800
|> Lines: 17
|> Message-ID: <85E06DA4-F9A6-4B20-B648-58E85450BF71@microsoft.com>
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|> Hi,
|>
|> I prefer if I can install SP1 before April, since I have an urgent need
to
|> test a fix which is included only in SP1.
|>
|> Surely there must be a way to uninstall a language pack that is not
|> required, e.g. removing entries from registry, deleting files etc. ?
|>
|> Thanks,
|> Tim
|>
|> "cfelix" wrote:
|>
|> > Additional languageas to the five stated will be available in April.
|> >
|> >
|> >
|>