PCI or AGP?

There are two basic types of graphics card - those that use the so-called PCI slot and those that use the newer AGP slot. If your motherboard has an AGP slot, there is no reason not to purchase an AGP graphics card, as these are generally faster, newer and the price premium is virtually non-existent.

Picture quality

Not many people think about the picture quality of their graphics card. Generally, the really cheap graphics cards provide terrible picture quality and so you should avoid all those cards that appear to be a bargain at Rs. 1300 - they're not. However, most popular graphics cards by companies like ATi, Matrox, Creativee and so on have very good picture quality.
For some people, image quality is very important (they generally use resolutions of 1280x1024 pixels on large monitors). Here a card such as the Matrox G400 is a good choice, while the true professional will want the Number 9 Revolution in it's latest incarnation.

Built-in 3D acceleration?

Most cards these days claim to offer some level of 3D acceleration, but it's speed and quality varies greatly. You should only need 3D if you're into games or professional 3D work. For games, cards based on the GeForce 256 Pro chipset provide the ultimate in performance at wallet-friendly prices. For people who prefer a top-notch 2D card with some 3D capabilities thrown in for good measure, a Matrox G400 or an ATi Fury 128 with 32MB should be a good compromise.

TV output?

If you play lots of games and have a big TV near your computer, a TV output can help enhance your gaming experience. TV output obviously also has applications for presentation work.

What if I just need a standard card for business work?

Then you need a card with at least 4MB RAM, preferably 8MB. Cards such as the Matrox Productiva or ATi Expert series provide exceptional value for money.