I have a Nikon D40 and would like to take photo's of high school basketball games. Of course they are played indoors under halogen lights I believe. I need a lens that is fast enough that I can use to zoom in and take pictures without a flash but won't be blurry. Any suggestions?
Then you are asking completely the wrong question.. a lens doesn't change the shutter speed, and you need a high iso film.. 400 or 800 is what most sports photographers used.. (or digital equivalent) and a fast shutter speed to achieve good light levels with minimal blur. After that it's a matter of personal choice... I did a project involving taking pictures of street girls at distance under streetlights.. for that I used an iso 1600 b+w film and set the shutter on between 1/25 and 1/200 depending on my best guess of movement and ambient light levels... turned out brilliantly grainy.. as very fast film should. so for your use you need fast film and fast shutter settings.. iso 400 to 1600 and shutter in the 1/250 range is good.. digital cameras specify such things in the blurb... lens is totally unimportant as long as you get up in the 10mp range.
So a D40 wouldn't take good enough pictures because it's only 6mp? I thought if you had a lens like f1.8 or so I could let enough light in even with a fast shutter to and no flash to help prevent blurring. I'd hate to have to buy a new camera also.
I don't know what a D40 is.. I'm old skool with photography. under indoor lighting a 2.8 should be fine especially with digital images.. or any actually where you can twiddle with the exposure afterwards. My husband is the guy to ask about such things.. I was a video camera operator rather than a stills photographer. You will get better answers on a specifically still pictures oriented website.
Lets say you have f4 lens and you get correct exposure on iso 800 and shutter speed of 1/125. If you change to a f2.8 lens, you can drop the iso to 400 OR shutter speed to 1/250 and still get the same exposure. So faster lens gives you faster shutter speeds if you choose to do so. edit: If you can tell me your current lens and what iso, aperture and shutter speed you are using, it would be easier to help...
if you're still interested in photography then why don't you join up with a Photography meetup group on Meetup.com. That's how I learned my photography skills and you can see some sample shots here: http://www.flickr.com/photos/27531361@N08/ your D40 is now a 4 yr old camera. for it's time it's capable of doing a lot..... but compared to the newer cameras yours is now obsolete. It's ok..... it still works. just that your speed of frames per second is slow so don't expect super crisp shots.... high shutter speed will do the trick but you will have to up the ISO to get a decent shot and the noise might be too much. Don't know ...... I have a Canon 5D Mark II. newer features that makes it easier to use than your D40. Mine is more for landscape because it's a full frame sensor where the fast cameras are the crop cameras...... but I have taken great sports shots.... check out this: http://farm4.static.flickr.com/3090/3119850063_18c5a539c7_o.jpg can you say TRIPLE! ANYWAY........ it's just the fact that you need to use your meter showing you levels of exposure! also keep in mind the light..... you said FLORESCENCE ..... set the white balance to that... I'm sure there is a setting for it! It could mean all the difference in your shots. good luck..... I know I responded 2 months later but this is good advice.