The first thing you should do is download the files below. Do this by clicking on the download link below. The file you download will contain a cracked version of NFSU2. It will also include the software you need to patch the game.
After you have replaced the original speed2.exe with the cracked version. Go back to the NFSU2 Widescreen folder and open the folder called widepatcher. Here you will find the uniws tool and patches file.
If you cannot set the resolution from inside the UNIWS tool. It means the speed2.exe file is not cracked. You need to go to the other speed2 files in the folder you downloaded from here. Extract them and repeat the process from step 3. However, you do not need to patch the game to v1.2 again. 2b1af7f3a8