You left the door open for us geeks to recommend systems that would make us drool by not listing a cap.
However, I'm going to assume that with 5 children (oh my!) that every penny counts. Thus, I'd suggest the Emachines T6212. At $579.99 (excluding the monitor, printer, etc), it's decently priced and packs enough power to last you a few years. However, you'll probably be able to find a better deal on, say, an HP, by searching the loacal circulars.
For a system that will last, look for one with a processor that supports 64-bit (either the AMD Athlon64 or Intel 600 series). Get a decent sized hard drive for all your music (160GB+). Audio and video/graphics cards would be nice, but aren't required for your needs (the "integrated" setup would be just fine). Finally, make sure it has a DVD burner for backing up all of those school projects and other data.
However, be aware that even a top-of-the-line system may be considered obsolete in 4-5 years. Your best bet would be to get a low- to mid-range computer, and either upgrade it or replace it in a few years with the money you saved.
As far as reliability, it's anybody's guess. Emachines (known for budget systems) used to be a little nothing, but has become quite good, especially since it was bought by Gateway. HP/Compaq is a good company with very competitive pricing, but you'll find a buggy system every now and then. Dell, Gateway, Sony, etc are more expensive for what you get, but their systems are a little more reliable. Just make sure you pick up an extended warrenty to cover any problems that may come up.
Hope this helps,
John
Would truly appreciate any advice I can get. I need to buy a desktop and here are my needs and non-needs: Gaming: children?s games, both software and Web, and I do mean children?s games, not any adult targeted games, A LOT of web usage (both for personal and business, but definitely more for personal), excellent reliability history as I have 5 children and can?t afford the luxury of buying the latest and greatest every time new technology is out. Also, music downloading both to MP3 player and cd, photo and video editing, but very minor, nothing too complicated. Money right now is not much of an obstacle as I will splurge on this PC to get something that will last me for at least 4 yrs. Again, thanks so much for the best advice you can give.

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