IMO, the second one will last longer while the first will probably hit them before they hit you, your best bet is to test them out in a battle.
1. You have it backwards. The second one is the speedy one, and the first one is the Wall-ish one.
2. I've already come to that conclusion myself. The reason I'm asking for opinions here instead of just playtesting them myself is because honestly, raising a Togepi to a Togetic is a pain in the ass in and of itself, so I'd rather only do it once. Plus, I only have two Shiny Stones in my SS inventory, and I'd like to get a Roserade at some point down the line.