Windows 7 - task manager processes

after some extensive scans with Prevx & Microsoft security essentials They've come back with the all clear.

However after some virus troubles, there are some processes left I'm rather suspicious of. I've done checks on them with free online scanners but I'm still left unsure.

processes are;
* csrss.exe
* nvvsvc.exe
* winmapin.exe
* winlogin.exe

what makes me slightly suspicious of them is none of them will let me open their file locations, nor view properties all other processes will but none of them are using cpu and none of them are running double instances.

Any suggestions wouldn't mind viewing a healthy windows 7 task manager processes, will look for more info

Regards

Watch this post and refresh. I will post as I find out.

Csrss.exe file description
Productname: Microsoft® Windows® Operating System
Description: Client Server Runtime Process
Company: Microsoft Corporation File size: Various


Productname: NVIDIA Driver Helper Service, Version 175.76
Description: NVIDIA Driver Helper Service, Version 175.76
Company: NVIDIA Corporation File size: Various

The last 2 look like legit windows .exe.

Is it winlogon or winlogin?

so far these are ok

Those are valid system processes provided they are in C:\Windows\System32. Type the name(s) into the start/search field and they will show up. There you can look at properties. If they are not in the system32 folder, they could be maware. Then you should Google them to find more details.

is it normal for critical services to show no user name information or description, nor be able to open file location or show properties?

Do I need to run some kind of system critical file repair?

I have the same situation for some processes. So it does not seem to be unusual. But don't ask me why and what the scheme is. I don't know.