I don't think I would, at this point, reccommend Gothic I - it's very dated, and Gothic II offers a similar experience in much more polished form. (though still not without rough edges)
Gothic II is, in my opinion, one of the best CRPGs ever made. (warts and all) The Gothic fanboy community is incredibly obnoxious - every times someone says anything suggesting making the Gothic games more user-friendly and more accessible to the typical gamer, there are howls of outrage from people afraid of losing their "elite" status if the mobs of the unwashed actually start playing as well... But you definitely shouldn't let that and the fact the game can be hard to learn at first discourage you from trying.
The biggest selling point of the game for me is that the world - while not large compared to something like Morrowind or Oblivion - is extremely detailed, and much more alive than the ones in those games. Exploration is rewarded in spades, even if the game can be extremely unforgiving if you stumble across things you weren't ready for. The game also does a good job of rewarding different character choices - you almost never have the "good, neutral and evil" dialogue options that steer you into a quest - instead, you'll often be surprised that resolving something in a particular way had consequences you didn't expect. (or opens up some new options)
Combat has its good and bad sides... As orangefruitbat says, it's initially rather clumsy and difficult, but that's because your character is unskilled. There are some things which are important to keep in mind, if you want to have a better starting experience:
1. Choose Gothic I style combat from the options menu if you want to see the combat work as intended.
2. Remember that combat is more about timing than anything else. Rapidly hitting the attack key really doesn't help. You need to time your parries and combos.
3. Different enemies actually require different tactics. For example, goblins are annoying little bastards that'll swarm you and try to get behind you, whereas orcs tend to rush straight in, working up a slow and massive swing with a heavy weapon. Wolves are best taken on as directly as possible, whereas the evasive bloodflies will slaughter you early on if you just charge in - but drop like that if you go after them with a bow.
4. Fighting multiple opponents at once is a very bad idea early on, before you get better skills and gear. Get them strung out using the terrain, take one out with a ranged weapon, or just leave them be until later...
Finally, for someone just starting out, I actually wouldn't reccommend gettic Gothic II gold, if you can get your hands on just Gothic II - the game is pretty damn hard as is, and with the Gold expansion installed, it gets sort of... insane. The development team did too good a job listening to the psychotic fanboys on that one. (even if the extra content in the expansion is actually great - but it's a huge game anyway)
And if you do end up picking it up, and want more advice, let me know.