Nintendo 3DS XL Help/Questions/Buying Concerns

Before I go into my post, let me say that while I consider myself a gamer, I have always been behind my Xbox and my PC. I have not really been into Nintendo since my N64 (and even then, that might be the best Christmas present I ever bought). So, I will need some advice.

My Girlfriend and I's anniversary is coming up. She was talking about buying a present out of the box, something sappy, but not too romantic, and something we could do together. Fortunately, this conversation took place in Best Buy while we were walking past the kiosk for Mario Kart 8 (the only game I could see myself buying for the Wii U). She stopped at the Nintendo DS XL station and played Mario Kart, and another game. I was in complete shock. My Girlfriend is so anti-video games its insane. She was like addicted, and so we continued down the isle, and she picked up like 5 or 6 games she just absolutely wanted then and there. So, she brought up the concept and possibility of her buying a DS XL for me, and vice versa. So, rant aside, here are some of the bare bone questions I have.

1. Simply put, is it worth buying? Handhelds have never done well with me. My PSP was barely played, and my Vita just never hooked me in.

2. Games? I love Mario Kart, Mario Party, Super Smash Bros, etc. Beyond that, I feel like I would be really stretching my identity to find a game worth buying a system of this much.

3. What is the shell life of this system? PS Vita seemed dead on arrival (I will place the blame on the Nintendo's prowess). That being said, I don't want to buy another handheld that will be left in the dust.

4. Where is the best place to buy these at, and games? Best Buy had it for 200, and the average game was around high 20s and mid 30s. That did not seem right to me.

5. Would a non video game playing, fully responsible adult female really fall in love with something like this? I love spoiling her, and she seemed to generally enjoy it (she loves animation, Disney, cartoons, etc). Would this really do it? Or is this going to be under her bed one day?

I hate being that question guy, but honestly, covering the internet for these questions seemed like a neverending cycle of continuous 'I don't know' and 'what!?'. Please help, thanks.

1. Most definitely yes. It's a great system with a great library of games. Many people don't like the 3D, but you can turn it off. Personally I love the 3D-effect and have it always on. After a while you know exactly how to hold your 3DS to not distort the images when playing in 3D, and I never get headaches or something.

2. Pokémon X/Y, Luigi's Mansion 2, Zelda: A Link Between Worlds & Ocarina of Time 3D, Bravely Default, Mario & Luigi: Dream Team, Fire Emblem Awakening, Monster Hunter 3, MGS3 Snake Eater, Professor Layton, Super Mario 3D Land, Animal Crossing: New Leaf, Donker Kong Country Returns 3D, Kid Icarus: Uprising and many more.

3. The 3DS is doing extremely well right now. It started off slow, but right now it's a killer system like any of the previous Nintendo handhelds. It has a vivid and diverse library of games and will surely be supported for years to come.

4. No idea. I'm a European (obviously also living there) so can't help you out here.

5. The system has games to cater to both gamers and casuals. I'm sure she will find enough to keep her hooked.

The system itself also has fun things to offer even without a game cartridge in there. There is streetpass, which in combination with Miipark (standard free software on the system) makes for quite a few hours of entertainment as well.

You can't go wrong with a 3DS imo.