symbols list microsoft office word 2007

By "symbols list", do you mean the symbols on the Insert > Symbol dropdown, or the contents of the dialog you get by clicking the More Symbols item? The set of symbols in the picture below is the default if you've never inserted any symbols through the dialog. If you have used the dialog, the symbols you selected there should start appearing in the upper left corner, pushing the defaults off the end of the display.

I'm not sure whether a repair of Office 2007 would fix either of these situations. If the problem is only in the dropdown, you can revert to the default by deleting the SymbolMRU entry in the registry key HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Common\General. The entry will be recreated the first time you insert a symbol from the dialog.