Your poll is invalid. You are offering two extremes as answer, but the truth is in the middle.
In general, photography is an art form. There are no absolute rules, so I cant give them to you. You can break any rule I give below, especially when you know what you're doing, i.e. you know why that rule exists.
- Are kit lenses good for photography ?
Any lens, even the worst in the world, is better than not having any lens. You need a camera and a lens, otherwise you cannot do photography. Your gear also dictates the conditions you work under.
(However you could do a camera obscura quite easily so the worst lens of the world is not THAT hard to get. If the worst lens is even the camera obscura. After all, in many respects, the camera obscura is actually quite fantastic, even ideal. Its just hella dark and hella blurry).
- What are the advantages of kit lenses ?
Depends upon the lens; the advantage of the Nikon 18-55 is its cheap, lightweight, offers some limited macro ability, and if you avoid the extremes of the focal lengths and stop it down a bit, the image quality is quite decent.
- What are the disadvantages / limitations of kit lenses
Depends upon the lens; the disadvantages of the Nikon 18-55 is that its dark, plastic build, and the image quality drops at the extremes of the zoom range, and while the bang for the buck is quite decent its not really good yet. Most importantly its very likely not a lens you will keep using once you have better lenses. In this respect, its a waste of money. As they say - poor men buy twice.
- What type of photos can a kit lens not take.
You can take any photo with any lens ... but the results might not be satisfactory to your demands in quality, desired framing etc. Thus the 18-55 doesnt offer:
1. Real macro. Real macro lenses will allow you more magnification than the 18-55, thus allow more resolution of small subjects.
2. Shallow depth of field. You are limited to 55mm f5.6 - lots of stuff will still be in focus.
3. Autofocus speed. Compared to better lenses, you will miss a lot of shots if you would try sports with this, because the autofocus performance isnt that great.
4. Ultra Wide angle, though you can help yourself by making a series of photos and combine them in the computer. Wont work with non-static subjects (well, it would be possible, but the results will be ... interesting)
5. Telephoto beyond 55mm (82.5mm full frame equiv), though you can "digital zoom", i.e. crop, even if that loses resolution quickly.
6. Lowlight. With 18mm (27mm full frame equiv) f3.5 you cannot collect much light with this; other focal lengths are even darker. Thus with little light and moving subjects you will need quite high ISOs and get a lot of noise in the picture.
7. Image quality. Even if with proper useage this lens can produce quite good results, there are definitely lenses which offer more.
- All you need are skills and techniques.
No. If you dont have a camera and a lens, you cannot photograph. End of story. And the best photographers will have the best gear. Because even if skill is more important than gear - combining best skill with best gear will give best results. However, what cameras and lenses will help you best to get results changes wildly with what you actually want to photograph, and your personal style and preferences. For example if your field is social photography (aka street photography), all you might ever need is a Ricoh GR compact camera with a fixed 28mm equivalent lens, available for $400 used. The camera is very stealthy and nonthreatening, its operation is almost completely silent, and the image quality - especially of the lens - is excellent. On the other hand, if your field is sports, or wildlife, your gear might be worth tens of thousands of dollars, and your performance will drop drastically with lesser gear than that, because then you often cant get the shot, since your gear is unable to get it. Another example, a landscape photographer might only have quite dark lenses, but they will want a tripod and various filters. Another example, a studio photographer might also only use quite dark lenses, but they'll have a ***load of lighting gear and a special place aka studio for their photography. Both landscape and studio photographers might use medium format, though, and with digital that means extremely expensive.
See the first sentence ... what "best gear" really is is completely subjective.
- No, just get a new lens.
Absolutely not. You already have it now; milk that lens for all you can. Dont get a new lens until you actually know what you need.
I would like to do a story about that: when I started photography, I kept buying more expensive compact cameras, and finally my first DSLR, a Nikon DX. Then I computed how much money I had spent on photography in total until this point. Turns out I could have comfortably afforded a full frame camera and a prime lens trinity from what I had wasted on a couple low quality compact cameras and an entry level DSLR plus some lenses.
Thus my advice is: do NOT buy the next camera just because it has some minor upgrade. Save the money.
Do NOT buy the next higher lens, like a Tamron 17-50mm f2.8 VC, even if its better. Save the money.
Instead milk your current gear until you know what you really want, then check out whats the best gear for your needs, then save for that gear. In short, absolutely avoid the "the poor man buys twice" rule. It will cost you a LOT of money.