MS Office 2007 installs just fine under Ubuntu 12.04 using wine 1.4. However Powerpoint will fail to start until you tweak wine a little.
Go to Applications > Wine > Configure Wine > Libraries. In “New override for library” type: “riched20.dll”, and click “Add”. With the new “riched20” file, click “Edit” and select “Native (Windows)”.
Powerpoint should now start as expected. Thanks to the fix for omgubuntu.