sort the "rollup" in group by

try like using temporary table

 SELECT * 
 FROM 
 (
     SELECT country, sum(id) as cnt 
     FROM mygroup GROUP BY country WITH rollup
 ) t 
 ORDER BY cnt;

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Have you tried putting the order in the grouping?

SELECT country, SUM(id) 
    FROM mygroup 
GROUP BY country DESC WITH ROLLUP;

Should return:

+---------+---------+
| country | SUM(id) |
+---------+---------+
| India   |      14 |
| China   |      74 |
| NULL    |      88 |
+---------+---------+

http://dev.mysql.com/doc/refman/5.0/en/group-by-modifiers.html

You can try this query:

 SELECT country,id
     FROM mygroup GROUP BY country ASC WITH ROLLUP