The vast majority of monitors on the market are lightweight, flat-panel LCDs. They come in a variety of sizes including the types of monitors listed here. The smaller monitors suffice for office work, but if you watch a lot of media or play games, you might prefer a monitor with a larger screen.
If you're really pressed for space or can find a particularly good deal, a 17-inch monitor could provide enough screen real estate for you. But 19-inch and even some 20-inch models don't cost much more.
For spreadsheet work or home photo editing, a 19- to 20-inch monitor offers a good amount of screen space for a reasonable price.
This is the sweet spot for gamers and media fans. You should be able to find a monitor with very good display quality for under $300.
Prices start at about $300 once you hit the 24-inch mark, but hard-core gamers and multimedia mavens looking for a big screen for watching movies and TV shows will appreciate this size.