I don't think that it is a good idea to reset the auto increment primary key indexes in your table as it can cause many problems.
The database doesn't really care about sequential values. Is there any specific reason for doing that? Think again and ask "why do you need to reset product ids?"
Primary autoincrement keys in database are used to uniquely identify a given row and shouldn't be given any business meaning. So leave the primary key as is. If you really need the sequencial data in every row then you can add another column called for example
product_count. Then when you delete a record from the database you may want to send an additional UPDATE statement in order to decrement the product_count column of all rows that have product_count greater than the one you are currently deleting.
But if you still want to make new product add at the place from where an ID is deleted then you might want to run following SQL command through terminal or phpMyAdmin.
Before doing this don't forget to take the backup of your database.
SET @num := 0;
UPDATE name_of_your_table SET id = @num := (@num+1);
ALTER TABLE name_of_your_table AUTO_INCREMENT = 1;
Product table can save upto 9999999999 product ids. Do you really think that not resetting the product IDs is a problem?