17 R1, reformat question, Windows 8 or Windows 10 Pro?

The main question is should I go directly to Windows 10 or should I install the Windows 8 first? 

• I am out of warranty since 2015 and heading to the time when I need to reformat.
• I have a USB with the windows 8 that the laptop came on and I have a full licence and serial number for the Windows 10 Pro that I was forced to buy when the "Free windows 10 upgrade" bricked my entire computer. 

Other Questions?

1. What problems am I likely to encounter?
2. Is there anything special I need to do for that 8gb card? 

Hardware

• Alienware 17 R1
• SSDR, 80, S3, MCARD, INTEL, Pentium 4 Prescott DT, 3.0GHZ, 1 MEGB, 800FSB
• 16 GB RAM
• AMD Radeon R9 M290X with 4GB GDDR5
• 2 1tb Hybrid drives

I would buy a new alienware but I don't think it's worth it.