Yes, That HP is probably going to be a good buy. even though the i5-2400 is a few generations old, it still screams. I have the i5-4440 in an HP unit and there really isn't much difference from the 2400 in the IPC (instructions per cycle) .. The only bummer i5's were the first generation.
I went with Windows 8.1 myself, as I remember from the olden days how the experts advised to stay one Revision behind, If you add the classic shell add-on, it really is a fine OS, if you must use windows.
I may give Win10 a go after the next Windows release happens...
Win8.1 is available from the MS site easily (the win7 iso is tough, it will reject, but the win8.1 sails)
https://www.microsoft.com/en-us/soft...ad/windows8ISO
You just need to create a file and put it in a certain folder to bypass activation.
https://superuser.com/questions/4984...-a-product-key
The torrent networks are saturated with Windows downloads of every type, but i can't really ascertain how that works in the end.
I am a Linux man myself, I only use Windows if i have to and even then i sure as hell am not going to connect windows to the internet. It is good to have it in dual boot so you can use it for Windows exclusive programs. and i got stuck with a few of those unfortunately