The 18-105mm is the standard kit lens that comes on the higher end DX cameras. It's a decent lens and covers a good range for a 'walk around' zoom.
EDIT: Bear with me while I philosophize some on this subject . . . .
I like to buy neat electronic gizmos, gadgets and stuff, and I suspect I'm not a lot different from most of the members on this forum. But, photography is an area where you can spend a LOT for not much gain.
Bottomline: you can't buy experience or skill.
Where I'm coming from is this; take a look at my gear. My main camera body is a D5000 (mid level body now 3 generations and soon to be 4 behind) and several decent 'consumer grade' lenses. Why?
Why don't I have a D7100 or D600, or even D800 and a bunch of top grade lenses? I'm not rich by any means, but it isn't because I couldn't afford them.
The reason I still have and use my current stuff is because my D5000 is still a better camera and my lenses are still better lenses, than I am a photographer.
If one of my pics turns out lacking that special something (and most do) it isn't because my camera and lenses weren't up to the task and they failed. It is most of the time because of me, a failure in technique or creative eye. I can't buy those, but am slowly improving in both. When and if my equipment becomes the main reason for something missing in my photos I will upgrade. Heck, I intend to upgrade anyway, just not in a big hurry.
The point is, the D7000 is a wonderful camera (the Canon alternatives are wonderful as well). It won't let you down. The 18-105mm is a very good entry level lens and quite cheap packaged like this. It will do you wonders while you learn what tools (lenses and bodies, etc) that you really need to suit your shooting and style. Honestly, the D3100 for half as much would suffice to start (but you wouldn't be happy with it, nor would I).
So, the best advice I can give is to go slow and not over buy until you know what you really want and need.
Cheers,
RavingMac
(Mike)