Excellent choices overall! There are some ways you can stretch your budget further and get almost the same performance.
1. Keep the motherboard. It's worth the cost.
2. Go with a mid grade duron or thunderbird cpu, rather than the 1ghz. You can save $150 there easily and it can be upgraded without having to change your software configuration down the road. Also, you can overclock pretty easily with the above mentioned motherboard. I've followed your posts, and from what you've probably picked up, all you need is a gorb and some arctic silver compound to go to 1ghz with a $100 cpu.
3. Keep the hard drive. It's worth it for the best.
4. Keep the sound card. This one is an amazing value. (as the name says) Have used 2 myself.
5. Might be cheaper to go with a standard us robotics faxmodem. The performance pro is optimized for online gaming if I'm not mistaken? It would be better to invest in cable or dsl if you're really serious about online games.
6. Keep the floppy. Never know when you might need it. I think I used mine at least 3 times this year!
7. Stay away from the CL burner. I have read bad things about them and have had personal nightmares with them too. That company should stick to sound cards, as listed above. Best bet would be to go a few extra dollars and get a plextor burner and a good cd rom or dvd rom to copy discs on the fly. If you don't think you'll make many disc copies and will be only backing up data, a burner made by hp is a good, cheap investment. They're priced pretty low and are reliable.
8. Good choice for a monitor. I would not suggest scrimping and going with a 17". The sweet spot for pricing is at the 19" level, and a 17" would not be worth peanuts when you try to sell it when you upgrade to a 19" down the road.
9. The speakers are good, but if you can, forego them all together and use your home stereo. A $100 home theatre receiver and speaker set will sound way better than these. If you're into mp3's or are going to get a dvd rom, it's worth it to go this route.
10. Not a bad mouse. I have personal tastes, so buy one locally. If you don't like it, return it and get a different model. Try as many as you like until you find one you like best. I'm biased because I like opticals, but I hate anything that is not cordless. Logitech makes ones that are precise, but the scroll wheels suck. Microsoft makes theirs kind of flimsy, but with good scroll wheels. Try them all out and keep the one you like.
11. Same goes for the keyboard. I prefer a cordless model, but like the layout of the natural elite for typing. Buy locally so you can return what you don't like.
12. Go with a geforce 2 mx model if you're not totally serious about gaming. It will do fine with current and next generation games and it's cheap. If you are a serious hardcore gamer, spend the extra and go with a geforce 2 or geforce 2 ultra card. Unless you play 6 hours a day, the extra cost isn't worth it. The video card will have to be upgraded in 6 months anyway to stay state of the art. If you're serious with DVD, go with an ATI raidon instead. The dvd playback with this card is better than any other manufacturer.
13. Stay with 128mb of ram for now. Make sure it's cas 2! Prices went low about 2 weeks ago, but are on the rise again. I think you can get by until after christmas, when prices should drop again. This way you can add more without having to change your software. However, if you're going to use any memory intensive apps off the start, like photoshop, go with 256mb right away. Minimum! If prices don't drop again, you're ahead anyway.
14. This is a dream case! Are you sure you need it? Unless this is a show computer, or you're going to pack 6 hard drives or 4 cd rom drives in it, it's not worth the extra cost. Best bet is to save and go with a mid tower and spend an extra $30 on case fans and a hard drive cooler. Just make sure any case you buy has a least a 300W+ power supply.
15. A good fan choice. Just be sure to use a silver transfer compound.
If this is a family computer, you'd better budget a little on the side for extras if you don't have them. Leave extra money for a printer, scanner, keyboard and mouse wrist rests, blank cd's, floppies. Also, make sure you have a decent desk to work at and a good chair!
Also, I've noticed that most of your prices are a little above market. If this is the pricing a local dealer has given you, shop around town and see if someone else can save you $100 or so. If you order the main components online, you should be able to save $300 to $400 off what you have here. That will make the $100 shipping charge worth it.
Either way, this is one hell of a christmas gift. Whether it's for you or someone else, it'll be fast!
Blaine