See if any of them have a system similar to what you want to buy. Check to see if they have had any trouble with their system or have ever tried to get technical support from the system's manufacturer. Also see if they have ever had any compatibility problems with any software applications or hardware. If they have had compatibility problems, see what steps they took to get the problems resolved and how long it took to get the system working again. And finally, see if they would buy another computer system from this company.
Lets talk about the wide ranging peripherals now.
You will need a multimedia kit, preferably a Creative Labs 64 bit sound blaster card with a nice set of surround speakers. You will need a modem to surf the web and you could check out the leading brands such as the Hayes or US Robotics 56k modems. Though let me mention that my GVC 33.6k modem which is Made in India has given me outstanding service and performed without a single glitch for the last 4 years. As for the printer a HP DeskJet or LaserJet or a Cannon would be nice. I do think that HP has the better service network in India though so you might want to keep that in mind.