>Try the following:

Dictionary<string, string> MyDictionary = ds.Tables[0].AsEnumerable().ToDictionary(dr => dr["KeyName"].ToString(), dr => dr["KeyValue"].ToString());

Excellent suggestion, Rob ... I wanted to mention an additional syntax one could use to cover the situation where your KeyValue, and thus the item in your dictionary, may not be a string:

Dictionary<string, int> MyDictionary = ds.Tables[0].AsEnumerable().ToDictionary(dr => dr.Field<string>("KeyName"), dr => dr.Field<int>("KeyValue"));

~~Bonnie