Bro, 4GB ram is not enough. IMO, minimum ram should be 8 GB.
Believe me, latest version of Windows 10 works too slow on hdd and 4 GB ram make it more worse. You'll get much slower 5400 RPM hdd.
Superfetch is enabled if you use hdd.
Superfetch preloads your frequently used apps into memory so that you don't have to wait much fully load a program. I'm using SSD and superfetch is disabled by default. Still Windows is using 2-3 GB ram by default. Because of that there isn't much ram left for Google chrome or any other browser. Only 5 heavy tabs such as Gmail, YouTube, twitter, Facebook, etc can use up-to 1 GB of memory. If memory usage reached 70-80 percent windows will start using page files.
Btw, ram and hdd are easily upgradeable so it isn't an issue.
If you're planning to use Windows 7, 8.1 or linux then 4 GB ram and hhd is fine. As, windows 7 or 8.1 doesn't uses much memory and you'll have enough memory to do moderate web surfing along with some other apps.
In short, windows 10 is heavy and because of continuously receiving upgrades it'll use more resource in future.
Another important thing, screen resolution. I'll suggest you go for FHD (1920 X 1080) display. It is not possible to upgrade screen resolution later.
These days every app size is increasing for no reason. Example, right click on Windows 7 or 8.1 on taskbar and right click on Windows 10 taskbar. You'll see Windows 10 context menu is much bigger than previous version of windows. Another example of increase in app size is Windows calculator, rufus and many more. And most important 'the web'. There is not much screen real state on HD (1366 X 768) display.