In regards to the audio card...not really my area of expertise. I'd do some research first and read the reviews before deciding on a particular brand/model. I see plenty of people using those X-Fi cards (or whatever they are called).
Higher resolution is always preferable with computer monitors as it means you can fit more on the screen and better IQ. TV's are slightly different...the viewer is going to be sitting far back and likely not focusing on tiny details (like small text) so a lower resolution is acceptable even on a larger screen size.
This image explains the various resolutions by comparison.
http://upload.wikimedia.org/wikipedia/en/e/e5/Vector_Video_Standards2.svgYou'll notice that HD 1080 (most common resolution used on HDTV's) is 1920x1080 which is the most common resolution for a 24" monitor. The true beasts are the 30" monitors which display a whopping 2560 x 1600.
The 1066 on the memory is related to it's performance. To really understand it, just read the
wikipedia page on it. Generally, the performance gains from upgrading the "speed" of the memory aren't worth the additional expense. Obviously capacity is still important, as is whether it is dual or triple channel.
Intel's OEM CPU's are preferable in the higher-end market where the consumers (hardware enthusiasts, businesses, etc) don't mind spending extra to gain additional performance. They are typically more expensive, but most are either already significantly more powerful than the AMD counterparts...or they have the OCing potential for higher performance. I am of course referring to their higher end CPUs (like the Core i7 series). In the lower end of the market (where value supersedes raw performance) AMD is a great choice. Where you draw line depends on a variety of factors.
Other things to consider include what features are available for the motherboards that match the CPU. For instance, the Core i7 series motherboards (The X58 chipset) all feature the ability to use both ATI Crossfire and Nvidia SLI natively. Additionally, all boards use Triple channel DDR3 memory standard.
One final note, a 3 Ghz AMD CPU isn't equivalent in performance to an Intel 3 Ghz CPU. There is a lot more to "it" than just how high the processor is clocked. There are benchmarks out there that can help you make an informed decision. Try to look for benchmarks that use real world performance indicators such as FPS or time taken and aim for ones that tailor to the programs you are using. Avoid relying on purely synthetic benchmarks.
