I have experienced 'touch screens' in two different situations.
Pub jukeboxes and also my tocca smartphone.
I find that I have to use a stylus (usually a small bookie pen) when trying to 'touch in' a text message, on the tocca, 'cos my fingerpads are too big.
The jukebox screen is big and inviting, and is a joy to use!
As far as home desktops are concerned, touch screens are not very practical.