If your output requires color, both laser and ink jet technologies can do the job. However, unless you need high volumes, the color ink jet is probably the better buy from a cost standpoint. Color laser printers have come way down in price in recent years, but they still command a premium. Their main advantage is still in their speed. Additionally, they often have more paper feed choices (business, legal, and envelopes, for example though there are some ink jets which offer these features, too.)

Either choice of technology will have a much slower per page throughput the moment your printing requirements include any graphics or images. If such is the case, as with computers, more memory in the printer is always better.

In considering the purchase of any printer, it is always wise to ask about the cost of consumables. For an ink jet, there's paper (special coated stock is sometimes required), and the cost of the ink cartridges (two for color printers black and color). Laser consumables include paper (they can happily survive on the same paper supplies you buy for your copier) and toner cartridges.

Also, check to see if your particular printer comes with a printer cable most do not. If you have to purchase one (most printers require a Centronics parallel interface), try not to settle for a mere 6' cable. If the printer is going on your desk and will be at your elbow, 6 feet is probably fine. However, it is not uncommon to locate the printer either slightly further away or and this is the part overlooked by many have to snake the printer cable behind desks and cabinets such that the path is greatly increased. We recommend at least 15' with 25' as a consideration (coiled, excess cable behind a bookcase doesn't hurt anything and gives you flexibility the next time you rearrange the furniture).

Buying and Maintenance

PC's have become common place, but like automobiles, some places are better to buy from then others. The general rules of thumb are quite simple:
If you are not too technically oriented and think you will need some level of hand holding, when something goes bump in the night, buy from either a well-known national chain or a local vendor of good reputation. The national chains offer good return, repair, and support policies. The local vendor is right there in town and earn their good reputation by helping folks just like you. Your choice often depends with which you feel more comfortable.

If you feel comfortable with the technology could you change out your disk drive if you had to? then you have much more latitude. As long as your source is reliable and has good products, then many  mail order vendors are worth using in addition to local vendors. The differences are usually cost, availability (or shipping time), and level of vendor support.

Maintenance contracts are a toss-up. It really depends upon your specific situation. If they are inexpensive and offer to repair or replace any broken part, they might be worth the money. If you have many PC's in your office, for example, you might want to consider just buying another PC and sticking it on the shelf, unused. If one of your PC's takes it on the chin, you have a ready spare at a cost, when compared to the cost of fixing the broken one and down time, might make sense for your organization.