So I've been using XP forever, and have been using the same copy of Server 2003/XP 64-bit for the last 8 years or so. But with the lack of support, and compatibility issues, it doesn't run as good as it used to, so I was thinking of upgrading to Windows 7. My plan is to keep XP as it is, on it's own hard drive, and just buy another hard drive to install Windows 7 on, and make the computer a multi-boot since I already have a dual-boot. So basically my main Windows which I use 99% of the time, and the other Windows, which is mainly just a backup, as it is installed on a separate drive in case my main drive goes bad.
But anyways, I'm wondering, does anyone know a good place to buy Windows 7? Newegg has it for $140, but there is a 10% off code which brings it down to $126, but that is still a lot, especially for an OS that only has 2.5 years of support left. That's for https://www.newegg.com/Product/Product.aspx?Item=N82E16832416804&ignorebbr=1. I've tried torrented versions in the past, but they never worked right, and would always ask for a product key, so I never stuck with them. Truthfully, I don't really like Windows 7. I love the layout and interface of XP, but like I said above, it's getting worse and worse to use safely and efficiently.
And as far as hard drives go, I currently use a WD Velociraptor, which I like because of the notable difference in speed compared to regular 7200rpm hard drives. So I was likely planning on getting another one with just more space like this one https://www.newegg.com/Product/Product.aspx?Item=9SIAAEE4RG6232&ignorebbr=1. My current drive is only 300gb, with 31% free space left, so 500gb would be plenty for me. But at the same time, I wonder about going with the SSD route, but then wouldn't I need a separate drive for my data if I use an SSD? Or could I have all my files, music, videos etc all on the SSD along with Windows and still work good? I know the general consensus is to use the SSD for programs, and a separate drive for all your data, but I don't want to have to buy 2 hard drives on top of Windows 7.
So would be the best course of action here, for the best/cheapest place to buy Windows 7, and what should I do regarding a hard drive vs. SSD?