Something like this is how you would use it in C# (implies ASP.NET, not plain ASP). You'll need to add using lines for System.Diagnostics and System.IO, too:

Process proc = new Process();
proc.StartInfo.FileName = "uptime.exe";
proc.StartInfo.Arguments = "-a";
proc.StartInfo.UseShellExecute = false;
proc.StartInfo.RedirectStandardOutput = true;

proc.Start();

StreamReader sw = proc.StandardOutput;
string myString = sw.ReadToEnd();
proc.Close();