I would put something togeather around the following lines if $500 is just for the computer it self.
AMD Athlon 64 2800+ Newcastle $120
This cpu is a decent choise and I take it over a celeron any day of the week.
ASUS K8N Socket 754 NVIDIA nForce3 250 $69
skt 754 decent motherboard from a solid manufactor. Not as upgradeable as a skt 939 but still have decent upgrade options. You got a agp slot so you could make it into a decent gaming system iif your needs ever changed. It also can hold up to a athlon 64 3700+ if you ever wanted to upgrade that.
Patriot 512MB 184-Pin DDR SDRAM Unbuffered DDR 400 (PC 3200) $41
512 Ram is good for tha average user you could always upgrade to a gig later. Never had a problem with Patrioit ram before.
ASUS V9400-X/TD/64 Geforce4 MX4000 $30
It will handle none gaming fine. Pretty much anything the none gamer do depends on cpu and ram and not video card. This video CAN NOT Game worth anything. It will allow you to use the internet as good as any video card.
Western Digital Special Edition 80GB 7200RPM $56
80GB should be enough for your needs
Lite-On Black 52X32X52X16 Combo Drive, Model SOHC-5236K $34
Plays dvds and write to cd and does it great. If you need a dvd burner then get a nec3540 instead of this otherwise this will be perfect.
XCLIO XClio 450BL ATX 450W Power Supply 230Vac $53
Great PSU for people that dont want to spend alot. If you do some reserch on it you acturally finds out that it is made by the same people that makes antecs PSUS. Making this a great deal.
CASE OF CHOISE FOR $50
just get any ATX case you want with out spending to much.
proberly going to cost like $40 for shipping which leaves it just under $500 when it all come and done.