SharePoint 2007

Ok, Ive done the typical student on work experience thing and messed up lol.

For the last two weeks ive been learning the new features of MOSS, and we needed to create a Report Centre for the Dashboards, and KPI feature. I noticed we were unable to create this because Excel Services wasnt enabled. So I enabled it and created a Reprt Centre, in doing this I some how turned of the feature for a new site to go into the tabs on the homepage, the option is no longer there. Ive no idea what ive done and im the only one in my office with any MOSS knowledge so cant ask anyone for help.

So, basically does anyone have any idea how I might of done this and how I can turn it back on again?

Thanks in advance

Steph