Renovating my kitchen!

1) Old stove (getting replaced) just has hose connected to gas pipe with no shutoff valve. Would it be safe and simple to install one myself with the usual precautions? (I've installed my own gas hot water heater before).

2) While my walls are open, I would like to run a new electrical outlet for a new dishwasher. Is there any danger or code preventing me from running a horizontal electrical line which crosses the vertical gas line? It just seemed like the type of thing I should check before I do it, since I've seen much sillier things be against code.

Thanks again!