Installed Office XP Pro after Works 8;excel files- XLS won't open

Hi,

I have Vista on my new laptop and was using Works 8.5 that came with it but
as it was not doing what I needed it to do so I installed Office XP Pro and
deleted the Works program.

I saved a s/sheet I have worked on for hours on my desktop and when I went
to open it it asked me to associate a file to open with it but every time I
select Excel from within Office under Programs, to get it added to the
options it doesn't add it and won't seem to recognise it. You may be able to
tell I don't know too much about this but desperatly need some help!

Does anyone have any advice?

Thanks