What's the best way of using a pair (triple, etc) of values as one value in C#?

Dictionary<Pair<string, int>, object>

Dictionary<Triple<string, int, int>, object>

int id = 33;
string description = "This is a custom solution";
DateTime created = DateTime.Now;

KeyValuePair<int, KeyValuePair<string, DateTime>> triple =
   new KeyValuePair<int, KeyValuePair<string, DateTime>>();
triple.Key = id;
triple.Value.Key = description;
triple.Value.Value = created;

KeyValuePair<KeyValuePair<KeyValuePair<string, string>, string>, string> quadruple =
    new KeyValuePair<KeyValuePair<KeyValuePair<string, string>, string>, string>();
KeyValuePair<KeyValuePair<KeyValuePair<KeyValuePair<string, string>, string>, string>, string> quintuple =
    new KeyValuePair<KeyValuePair<KeyValuePair<KeyValuePair<string, string>, string>, string>, string>();

struct Pair<T, R>
{
    private T first_;
    private R second_;

    public T First
    {
        get { return first_; }
        set { first_ = value; }
    }

    public R Second
    {
        get { return second_; }
        set { second_ = value; }
    }
}

public struct Pair<T1, T2>
{
    public T1 First;
    public T2 Second;
}

public struct Triple<T1, T2, T3>
{
    public T1 First;
    public T2 Second;
    public T3 Third;
}

int id = 33;
string description = "This is a custom solution";
DateTime created = DateTime.Now;

KeyValuePair<int, KeyValuePair<string, DateTime>> triple =
   new KeyValuePair<int, KeyValuePair<string, DateTime>>();
triple.Key = id;
triple.Value.Key = description;
triple.Value.Value = created;

KeyValuePair<KeyValuePair<KeyValuePair<string, string>, string, string> quadruple =
   new KeyValuePair<KeyValuePair<KeyValuePair<string, string>, string, string>();

public Tuple<int, string, int> GetSomething()
{
    //do stuff to get your multi-value return
}

//then call it:
var retVal = GetSomething();

//problem is what does this mean?
retVal.Item1 / retVal.Item3;
//what are item 1 and 3?

class CustomRetVal {
    int CurrentIndex { get; set; }
    string Message { get; set; }
    int CurrentTotal { get; set; }
}

var retVal = GetSomething();

//get % progress
retVal.CurrentIndex / retVal.CurrentTotal;

Dictionary<KeyValuePair<string, int>, object>

public class Triple<T, U, V>
{
  public T First {get;set;}
  public U Second {get;set;}
  public V Third {get;set;}
}