Good all around lens?

[greybeard]

Amazon.com: Nikon 40mm f/2.8G AF-S DX Micro NIKKOR Lens for Nikon Digital SLR Cameras: Camera & Photo

or

Amazon.com: Nikon 85mm f/3.5G AF-S DX ED VR Micro Nikkor Lens for Nikon Digital SLR Cameras: Electronics

in your price range. I'm going for the 85mm soon as I can afford it.

 

[DiskoJoe]

A friend of mine got that 40mm for his macro work. Says he really likes it.

 

[adichiru]

As others here I would also suggest a prime macro lens with the focal length that you consider appropriate for you and on the D5100 which is a APS-C camera.
A macro lens is [always] a very good lens for portraits. I have the 105mm f/2.8 G and it is absolutely great! You may want to go with the 60mm or, for less money with the above mentioned 85mm.

You cannot have a good macro lens and zoom in the same time.

You may receive advice to get the 50mm f/1.8 or f/1.4 which are good for their purposes but are not macro and I would not use them for portraits instead of the 105mm f/2.8 if I am not forced by some other reasons.

 

[lonewolfsx]

You say you want a zoom... are you totally set on a specific range?

I hate to create competition for myself as I've been looking to buy one myself, but the older Sigma 24-70mm f/2.8 Macro is pretty darn sharp and has "macro" abilities up to 3.8:1 at 70mm that's pretty good and offers a good aperture for portraits. There's one on KEH right now for $370 (EDIT: just got an email back from them, doesn't include lens caps? How the hell does that work??)

However if you want a telephoto zoom, your options are pretty limited in that price range, nothing offers any form of real "macro" or aperture numbers generally used for portraiture. You say you want it for portraits and macro... but is there some other use you need out of it that makes you want a zoom lens?