Thanks to everyone for responding so fast.
Joel, I used your option 2 and added a registry key to the “Run” folder of the current user.
Here’s the code I used for anyone else who’s interested.
using Microsoft.Win32;
private void SetStartup()
{
RegistryKey rk = Registry.CurrentUser.OpenSubKey
("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run", true);
if (chkStartUp.Checked)
rk.SetValue(AppName, Application.ExecutablePath);
else
rk.DeleteValue(AppName,false);
}