New PC build up and DAW upgrade

1) Cakewalk offer more basic versions from $99 (Artist edition).
 
2) a) Intel Series 5 processors might offer more internal data bandwidth for same cost of the AMD. Now that Intel have starting producing 8-core solutions themselves, 4 or 6 core solutions might be more financially feasible. As an AMD user myself I am not bias however my next cpu will be Intel based.
 
b) The motherboard with all the mod cons might look good although concentrate on storage and expansion. If you plan on a silent PC with plenty storage then you don't need SLI/Crossfire features per se.
 
c) Like I said above, if you don't plan to play games or you might just watch the occasional movie then a passive heatsink AMD or Nvidia GPU will do the job. Alas some chipsets will have built in GPU which are pretty decent. Even Intel Iris graphics should do the trick.
 
d) If you can Windows 7 or Windows 8.1, Windows 8 is a horrible release. 64-bit is a no brainer these days. 
 
e) Go for a computer chassis with plenty cable hideaways, cleanable filters and good airflow to maintain the systems reliability over time.
 
f) There's an argument for using factory installed watercooling solutions over traditional air/copper or aluminium coolers. What you don't save in money is saved in noise generation and greater heat dissipation. 
 
g) 8GB yes, more if you can afford to.
 
h) Power supplies are better if they are reputable and also have 80+ or better certification. Modular cost a bit more however let you configure how many connections you actually really need at the one time.

Before even thinking of SSDs, I'd add more RAM. 512MB is very little for a modern operating system to work in before you add a DAW on top. On a DAW you want to avoid Windows writing to the swapfile on the disk as much as possible because it takes time and that time often means dropouts.
 
As for SSDs, unless the laptop has a SATA interface built in then SSDs are pretty pointless as the drive interface itself will be a limiting factor in data transfer.
 
In a new build, personally I'd go with Intel rather than AMD for the cpu and motherboard chipset. I'd also price in a good cpu cooler and quiet fan and a quiet case fan - Noctua for example. Seasonic make good fanless power supplies though they aren't the cheapest on the market. Unfortunately for any computer component that generates heat the easiest and cheapest way to get rid of it is a cheap, noisy high speed fan so that's what you'll generally find on cheaper components.
 
As for graphics, the Intel on-chip graphics are OK but can be a bit slow even for dragging windows around the desktop. If your budget stretches to it I'd look for a low price fanless gpu. Doesn't have to be too powerful, and there are quite a few around if you look for them. Sapphire make AMD-based fanless boards at pretty good prices and some are quite capable - my DAW has a fanless Sapphire AMD R7 200 series gpu in it that can even cope with less stressful 3D games without problems.
 
As for operating system, 64 bit Windows 8.1 is where I'd go. having run Vista, 7, 8 and 8.1 on a DAW I'd say each release has got a bit better at handling real-time audio processing and generally a bit smoother, faster and lighter.
 
SSDs make sense as the system drive in a new build because they speed up access to data considerably. Also maybe for storing samples. As for spooling audio to and from, they are also good at this but the frequent writes may shorten their life (I can live with that, others differ - my current Intel SSDs have been in use 2 years and show no sign of slowing down yet). If you only want to use a single SSD then use it for Windows and applications and a big 7,200rpm HDD for everything else. Avoid the "green" drives which save power by varying their rotation speed, they are fine for many purposes but not for streaming multi-channel audio. Partition the HDD so that the first partition is half or less of the total capacity then use it for Sonar projects (the first partition is nearest the outer edge of the disk which means better sustained read/write rates). Use the rest for the documents, pictures etc. directories that Windows requires (you can move them from their default location on C:) and anything else you need to store.

Ya judging by those specs that's gotta be an old  IDE type laptop drive. Not worth spending money on. and if the RAM is not DDR 2 SODIM or newer you won't even find it.  
 
I'm not an experienced builder and if you lucky mabey one of those guys will chime in, But most of them sell pre built systems for a very reasonable fee which is a smart way to go if you don't have a lot of comuter knowledge at this moment. And by the time you learn every detail of what's available right now, something new will come along that makes it obsolete. But that said, you can save a lot of money bilding your own and for me it's part of my ultra nerd personality that makes me go there.
So the follwing is just what I did and by no means the right way to do things,,, but it worked. 
 
First you'll see that most Mobos are  gaming ( crossfire) and the price goes up accordingly. 
What I did was start at the lowest price point for 1150 intel and 97 ?  ( $ 79)  and work my way up, I made sure it supported all the things I was going to plug into it. Make sure it has 3 video options, 6 USB 2 ports 4 USB 3 pots etc. I also looked for the orientation of the SATA ports.
The processor you get what you pay for so just set a budget and make sure it to is 1150.
Memory is going to be $160 for 16 GIGs. You could start out with 8 and add latter.
 
There's more but I gotta run..