I'm undecided as to whether or not to buy into BTC, both pro and anti arguments seem equally persuasive to me. However if I do decide to buy btc there are some basic questions I'd need answered first by someone with btc experience/knowledge because I'm somewhat tech challenged and don't personally know anyone who knows anything about bitcoin.

First if I bought btc I wouldn't want to store it on an exchange like MtGox or whatever I'd want it secured on a thumb drive and off my computer. How do I go about doing that? I've never even bought or used a thumb drive before. So question 1 is how do I safely and securely download a wallet, buy bitcoin then transfer it to and securely store it on a thumb drive? (I'm using Windows 7). Also how would I actually pay for it, I'd have to withdraw from my bank account, right? How is that done? And how could that make it "anonymous"?

2nd question : if I had btc then if/when I want to sell it for GBP or USD, presumably using the thumb drive, then how would I go about doing that safely and securely?

Any help/information in lay terms gratefully appreciated.