I played the first one through and loved it. I'm now playing Witcher 2 and loving it as well.
If your concern is the plot and back-story, I think you'll do fine just reading the plot summary on Wiki
As far as importing a save game, it carries over a little bit of money and gear, but nothing that gives a huge advantage. You'll have earned more money and better gear in a few hours anyway.
The biggest issue I can think of is in understanding the mindset of the character, the game, and the world. The Witchers are powerful warriors like you'd find in other games, but that's not what makes them interesting/unique. Their specialties are knowledge of the many exotic monsters and their alchemy with potions (and traps and bombs in this case).
Reading/researching about creatures would be optional codex/lore in another game, but here it is part of the quests themselves. Potions, bombs, traps would be optional consumables in another game - and I personally rarely use them - but here they're critical.
Many people are struck by the difficulty of the game, and it's usually because they're trying to sword-fight their way through everything. If you really make use of the traps, bombs, potions, oils, etc. you should do just fine.
Lastly, understand that the character Geralt is not trying to be a heroic soldier. Unlike in comparable RPGs, you're neither a great hero nor villain, just something like a tough exterminator travelling from village to village cleaning up their monster infestations. Getting caught up in politics and wars is anathema to the cynical Witcher who just wants to be on his way to the next job.
I now found the function, it is called "use medallion" and mapped to the Z key (or Y in german). When using the medallion you highlight all items in the vicinity for a short while, although the highlighting effect is pretty subtle.
The use of the medallion also shows you places of power and highlights enemies.
Best Answer
Spoilers! Duh...
Serrit is probably referring to the fact that the three Viper witchers and Geralt fought the Wild Hunt together.
If I interpret this video (starting at 13:32) correctly, Serrit is talking about the time when Geralt was looking for Yennefer, who had been abducted by the Wild Hunt (in order to draw out Ciri).
It's explained in this video:
Geralt, Letho, Serrit, and the 3rd witcher from the Viper school found the Wild Hunt, and slaughtered a lot of them. they couldn't kill them all (which is one thing Serrit is referring to), so Geralt offered his soul in place of Yennefer's.
"The curse" of the Wild Hunt isn't that much of a curse per se, it's just that those buggers go around kidnapping people for their own purposes, and they're also tied to Ragnarök, which not even Viper School witchers want.
Sile knew, about the Wild Hunt and Yennefer, but she didn't want Geralt to learn. Why? Because Geralt and Yennefer's love was an important source of trouble for the sorcery lot, and right now Geralt was happy in believing that Triss is the love of his life and always been. Was Geralt to start hunting for Yennefer (hallo, Witcher 3), this would create a lot of complications for their "plans".
How did Sile know? Probably because of the Lodge of Sorceresses - they had a Nilfgaardian sorceress, Assire var Anahyd, who could inform them that Yennefer was in Nilfgaard. While initially reluctant to tell this to Geralt, Sile changed her mind in the end of the game (assuming you saved her, of course, and even then we already knew that from Letho).