let say I create a partition and on this partition I copy files that are not infected with any virus now I delete another partation
that has all my files and all my virusses.Then as long as the files I copied on the partation are not infected I should have no virusses right?
How about it depends. It depends on what the drive contains (does it contain a partition that has your host os) or is it a second drive. honestly, you are best off making a backup of it and restoring only the files off the backup and nuking the entire drive.
What if the harddrive in question has a system os on it, and what if that system os is the os that is currently running, and what if that system os has a rootkit or other malware that hides itself in the partition table...what then? The drive is still infected, and the partition is still infected.
The way I would ask the question (and answers are welcomed) would be like this:
Are there any viruses that, without the intervention of the user, can infect any partition other than C drive?
I've played around with a lot of viruses and have yet to come across one that, by itself, infects any other partition than C drive (where the OS resides).
I think there might be. Sometimes when your install a program (especially from Microsoft) files are often placed on the next partition. Office 2003 is an example where the MSOCache will go there by default.
I suggest you scan all your drives/partitions using both MalwareBytes Anti-Malware and Avira Antivirus Personal Edition (both free for home use). Run full scans.
You never know how bad your viruses could be. Even Word documents can get infected. Do things the safe way, and scan all files first before using them again. And do a backup of your system also, just in case.
Probably the easiest (and safest) thing to do would be to erase the hard disk using whatever utilities the hard disk drive manufacturer provides, reformat it, and then reload your operating system and applications from their original media and your data from your clean, uninfected backups.