(A.) Resize the web parts on your page to have a fixed width. This will fix that particular page, if you want to have every page conform to such a standard, you can try a different master template if you have enterprise version, otherwise you will have to open SP Designer or Visual Studio and edit the CSS to restrain the main width to fit your needs.
Edward J. Nelms | MCTS, MCP, DCSE
SharePoint Architect
(Q) I need to resize our portal so that it displays on PC's with a screen resolution of 1024x768 with out there beeing a horizontal scroll bar on the page. Any advice or suggestions will be highly appreciated. Thanks.