Sometimes when adding custom Web parts to a Sharepoint site, a script or code error will cause the whole page to become disabled and you cannot edit or remove the offending Web part. Fortunately, there is a little trick you can use to get around this. The trick is to add Contents=1 to the URL string which will bring up the Web Parts Page Maintenance page. For example, typing in http://myserver/default.aspx?Contents=1 will display
From this page you can then choose the bad Web part and delete it.