M1710 HD + OS Upgrade Noob Question

Okay, I did a search within this board and came up with only year-old threads so:
I'm looking to upgrade my M1710's current 80 GB 7200 RPM HD to this:
http://www.newegg.com/Product/Product.aspx?Item=N82E16822136280

While I'm at it, I thought I'd install Windows 7 Pro instead of the Vista Home Premium x86 I currently have. In short, I'm searching for a faster OS on a HD with greater capacity at the same or greater speed of my current drive, and the above is what I found. Now, my noob experience ends here, so I'm hoping I might be enlightened by those wiser than myself (admittedly, not that hard to do) in these matters.

1. Should I go for x86 or x64 in W7? I believe all programs I currently need are x64 compatible, so that shouldn't be an issue. Have all driver problems been sorted out? On that note, are there any drivers I should save on a flash drive before installing W7?
2. Perhaps this should have been first, but is that HD okay? Is the upgrade process as simple as I've seen in videos on similar models i.e. unscrew the encloser, slide it out, unscrew and remove the old HD, screw in the new HD, and screw back in the enclosure? I've upgraded my RAM, so I know I have the small screw driver required for these screws, but is there anything else I should be aware of prior to electrocuting mysel... I mean, becoming a little bit wiser?

My complete specs are in my sig.

I also mainly use the V20 Logitech external speakers. Does anyone have experience with these under W7? They're listed as "Compatible" on the MS website for both x86 and x64.

Thanks!