Sorry for a slow reply, running in slow mo currently, the whole house has come down with a stomach bug, and with my health it hits me like a pile driver, anyway you appear to have the wrong driver there, but no wonder you had trouble choosing, but as with all things it's about studying the small print, so delete that file you have, then go to my link (your took me to page not found), when you see the mass of files note they are in boxes, you want the 3rd box down called Fast Ethernet Network Card, next you want the 2nd file down called
PRO200WL Wake-on-LAN PCI Fast Ethernet Adapter, my hope is this link will do it, but if not following this instruction you should get the correct file.
This of course throws up even more issues, given what you found I went through to download the file to see what you would face next, and what a surprise there is even more confusion thrown in for good measure (Dell's site are no better), now the following link appears to be the file you need, BUT, you will need to read the label on the card, the page shows you what to look for, so hopefully once you identify this last bit of the puzzle you will finally get the driver, see how you go, but I've never seen such a hard time doing this before.
http://www.cnet.com.tw/download/pro200wl.htm
Now if we aren't confused enough your last scan shows yet another LAN, it may be possible this is the real card identity and they have just re-badged it, so if your up for a gamble (assuming this other one doesn't work), then we can try the driver for a Realtek RTL8139, this has again created many issues, I found it very hard to navigate to a download, maybe my settings are getting in the way, but eventually I was able to download the files using Chrome, in ie8 I was just redirected to audio drivers, so if this happens to you use another browser.
The link is as follows,
you need the top entry, to the right of the entry they offer 3 downloads, they are exactly the same download, they simply offer different servers as they are notorious for slow speed in my experience, and one may be faster than another.
The audio is curious, lets see if reinstalling\updating the driver takes care of that, go
Here to Dell and expand the Audio section, if the link doesn't work navigate to your system under the drivers heading, they have 3 links for Creative Sound Blaster, start with the 1st one (going down the list), then once that one is done move onto the next, the hope is the driver, and subsequent patches will get your audio back on track.
Now drives, you will get a sweeter result if you buy separates, WD is definitely the brand I would go for, I've certainly found it to be the most reliable one in my time, I have nothing against the unit you have selected, but if you can stretch that bit further you will get more for your money, I would suggest the
Western Digital WD1001FALS Caviar Black Hard Drive 1TB, last time I got an X Craft 360, but can't find them on Tiger, so something like the
Vantec NST-300SU-BK NS CX Hard Drive Enclosure - 3.5" SATA to USB, eSATA.
The spec is not clear on the one you chose, but my guess is it will have half the cache at best of the one I suggest, and it is USB only, the dock I suggest has eSATA, this means transfer speeds will be much better, although you may not have eSATA on your current system, it will stand you in good stead for you next system, and it you felt brave that unit also comes with an eSATA port (as best I can see) for putting into your system now, assuming you have an available set of header pins, then you can benefit from the faster transfer speeds from the start, so for not much more than you had found, you can achieve a superior result, hope that helps.