Yes, to both of your questions.
I can see why you'd be confused, since typically you can't hold the charge on a spell if you cast another spell. However, elemental touch isn't actually a touch spell. It's a personal spell that targets you. By casting elemental touch, you are giving yourself the ability to make a special melee touch attack for the next few rounds. If you cast shocking grasp afterwards, then you can make your elemental touch attack and have it discharge your shocking grasp as well. In addition, there's no reason that you wouldn't be able to use lightning for both. There are no rules about damage of the same type from multiple sources not stacking.
Be careful, though, that you cast elemental touch first. If you cast shocking grasp first, then casting elemental touch will discharge your shocking grasp to no effect, since casting a spell while you hold the charge discharges your touch spell.
Normally, you can't benefit from two different touch attack spells at the same time, because:
(Taken from FAQ for the Magic rules, see under Range: Touch, FAQ on the right):
If a spell allows multiple touches, are you considered to be holding the charge until all charges are expended?
And from the combat rules:
Holding the Charge: If you don't discharge the spell in the round when you cast the spell, you can hold the charge indefinitely. You can continue to make touch attacks round after round. If you touch anything or anyone while holding a charge, even unintentionally, the spell discharges. If you cast another spell, the touch spell dissipates.
Since Elemental Touch is not a touch spell - it is a spell with range:personal which grants a single attack an additional energy damage, and it lasts for 1 round per level. Seems like there's no problem with casting Elemental Touch, and a round later casting Shocking Grasp. As long as you hit before the Elemental Touch ends, you apply the damage from both spells to the attack.