The game was designed for 4:3 monitors. You may need community-made "Widescreen Fixes" to prevent the image from stretching.
If you are looking for the classic FIFA experience without the security risks of "free download" sites: FIFA 08 PC Free Download
Many sites offering "free full version" downloads of older games bundle the files with malware, adware, or "cracks" that your antivirus may flag as high-risk. The game was designed for 4:3 monitors