Building a new PC - help please

That's not too bad of a system for a start. A little tweaking will make it damn good.

CPU
I'd stick with the E6300 chip. Even at stock it either meets or beats anything AMD has on the table. I recommend spending an extra $20-$30 on a quiet heatsink. The boxed heatsink/fan that comes with processors are loud and crap. I'd recommend an Arctic Cooling Freezer Pro 7, due to it's low noise, awesome cooling, and price point. It rivals $60 heatsinks.

GPU
What games do you plan on playing with this new system? The answer could determine what video card you should buy. I'd go with a variation of the 7900 if you don't care about new games and/or DirectX10.

RAM
Considering that there is no price difference between DDR2 5300 and 6400, you should just get the 6400. You'll have a better chance of using that RAM in a future system if you upgrade your chip. I use Corsair and it runs perfectly. My buddy tried cheaping out a bit by going with the OCZ, and he had to RMA it.

Mobo
You have a lot of options here. There are two chipsets that you could go for: nVidia 680i or the Intel 975X. I'm a fan of the of the Intel because they have a reputation of being rock-solid stable. However, nVidia does pack a few more features into their boards. You'll be fine either way. (And yes, you'll probably find a board that has an IDE connector.)

Monitor
It's really up to you. I prefer widescreen. You could go with a good monitor by Samsung, LG, or Dell with decent specs and come out alright.

HDD
I'm a fan of Samsung hard drives. They run quietest and coolest, according to my own opinion and various other sites. I own 5 of these and they've been great.

PSU
You might want a slightly more powerful PSU. Antec has a NeoHE 430W, but also look at Enermax. Enermax is known to be the best.

Optical Drive
LG burners are some of the quietest drives, and have a good reputation. I've owned three of them and have had nothing but good experiences with them.

Sound Card
This is totally preferential. The load it takes off your CPU is very minimal, and that's only if you use the Hardware Mixing or EAX features in-game. I noticed a slight change going from onboard to my Audigy4, but I really don't know how much of a difference it made. An Audigy4 might be suitable for you. I spent only $50CAD on mine.

My 2¢.

Jam it back in, in the dark.

Originally Posted by Chairman Kaga

Since when were the 7900GS or X1950 PRO top-end cards? I don't consider USD$200 to be one. Maybe I should drop down to the 7600GS/X1600/X1650.

The X1950 beats out the 7900GS hands down. And they were considered top-end cards up until November when the 8800GTX was released.

Originally Posted by Chairman Kaga

There's a price difference between the 5300 and 6400. In Australia at least. Don't know if it's really worth it. Don't you have to tweak the bios to get the most out of the 6400?

xe.com says that our currency is nearly equal, yet your prices are pretty damn expensive. Maybe it's just the store your buying from? In Canada, there is only about a $40 difference between the 5400 and the 6400, which makes the decision a no-brainer. (Our RAM is also $100 cheaper, too. ) You might should be with the 5400 if you don't plan on upgrading your chip anytime soon. There isn't much in the way of future technology that would warrant an upgrade, anyhow.

Originally Posted by Chairman Kaga

What about speed wise vs Seagate and WD?

I've noticed they're right on par with the other manufacturers. Google around for some benchmarks and comparisons.

There's nowhere I can't reach.

Originally Posted by Chairman Kaga

What about the 5300? There's little difference in price between that and the 4200. But then a big jump to the 5400.

5300 and 5400 are the same thing, just named differently due to a technicality.

The price difference comes from the fact the stuff labeled as 5400 is Corsairs XMS2 model of DIMM, where the 5300 stuff is the Value RAM. By all means, get the 5300 for the cheaper price. You won't see any kind of noticable change between the two types.

This thing is sticky, and I don't like it. I don't appreciate it.