Here is a simple way to get to the web part page maintenance screen. This can be helpful if a web part customization is causing the page to error out.
All you need to do is append:
?contents=1
to the page URL. For example, if your page URL is http://sharepoint/Pages/Home.aspx, you can enter http://sharepoint/Pages/home.aspx?contents=1
From the maintenance page, you can delete problematic web parts:
Dan Myhre's Blog 