Vista - Need help with a Trojan infection

Hi, I have Vistax64 HP. I use Avast antivirus, and when i scan, it comes up that I have a trojan in both C:\hiberfil.sys and C:\pagefil.sys. I didn't know if I could just delete these files, or if that would be a bad idea since I know they are legit windows files. Any suggestions for getting rid of this virus?

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C:\hiberfil.sys, when you try to delete the file, but Windows won't oblige. Windows has a feature called Windows hibernation. Instead of shutting down and restarting your computer, Windows takes a snapshot of everything running on your system, copies it to the hard drive and then turns off system hardware. You can delete that file by disabling the hibernation of the system. And once you have done that restart the system & the file would get automatically deleted.

C:\pagefile.sys : Try to disable the virtual memory of the system.

And then run a virus scan & see if the issue gets fixed or not.