Have you installed v1.07?
http://linkscorner.org/files/patches/Links_107.zip Have you installed the nVidia/Win7 patch?
http://www.lspn.net/downloads/Links2k3_nvidia_win7.exeIf these have both been installed properly, you should be able to select the resolution in the game (Options, Graphic Options). While I haven't seen the error message you're getting before, the following steps have resolved the issue where the game reports the video card is too old to run the game:
1. Click START, type regedit and then click on the REGEDIT program. (click OK when it asks to allow the registry editor to make changes to your computer).
2. On the left pane, click the > next to the branch called HKEY_CURRENT_USER.
3. Continue expanding the following branches by clicking on the > next to them:
Software
Microsoft
Microsoft Games
Links 2003
4. In the left pane, under the Links 2003 branch, select DisplaySettings.
5. In the right pane, find the key named Software and ensure it is set to 0. (If it isn't, double-click it and change the value from 1 to 0).
6. In the right pane, find and double-click the key named Windowed in the right pane and change the value to 0 (if it's already 0, then no need to change it!).
7. In the right pane, find and double-click the key named Mode in the right pane and change the value to 3.
8. Close the registry editor and start Links.
The game should start in a window that is at a resolution of 1280x1024. After the game starts, you should be able to adjust the graphic settings to your preference (windowed or not, and resolutions up to 1920x1200).