Hi again!

I am going to buy a couple more of BTC, and invest in it on monthly basics. Until now, I am using Bitcoin Core on my local PC and some lightweight wallet on my smartphone, but as I would like to hold bigger amount of BTC for a longer period of time, I am concerned about safety.

My idea is to buy an old laptop, that will be completely offline (turned-off/unplugged LAN devices). I'd use it to keep my private key and sign transaction with. I would communicate with it only with USB stick to migrate signed transactions outside. Private key would be offcourse saved on a paper copy(ies) as well.

Questions:
1. Is this do-able? If so, how can I sign transaction on an offline machine? Which tools should I use?
2. Could I do it with a tablet as well? Do you knwo any tools?
3. Do you see any security issues with this approach?
4. Do you know any tricks, to make paper copy of PK more secure? Less readable?

And yes, I did consider Trezor, but I decided to do it the other way.

Hi all!

I have a question about how long does it take to process a transaction. I read a lot about it, nevertheless, I am still confused.

There are two transaction in my wallet, that are still unconfirmed. One is very small, 684 satoshi, and it is idle for nearly a week. I guess it is possible for such a small amount. But the one that concerns me more, is 0,1BTC + 170b fee. I sent it more than seven hours ago, it is marked as "High Priority", it is 520 bytes in size, it has a fee, and yet - I am still waiting. Is it normal for such a transaction? Can I avoid that next time?
Transaction id: 9cd909bb8246dd7307b354279b1212f62b2780dfd901d64cea9f6db75f88da8f
My wallet: Bread Wallet on iPhone 4s

If it is normal, then please, explain me how can I pay with BTC in any store/bar, if I have no control if my payment will be received the same day?