help please

[mateyav]

Could someone please help me with your opinion if what I had is a virus or just a false positive.

I have AV 4.8 home, win XP

the other day I was watching a video on a streaming site with firefox browser, when I got a warning that there was a win 32:trojan-gen found in one of the google files. I scaned the laptop and AV found 64 other win32-malware-gen or win32:trojan-gen

I put them in quarantine. I rescaned some of them the same day and it said it was malware-trojan.
The next day I updated AV library and randomly rescaned some of the files and it was clear - no virus found.

most of the infected files come from C:System Volume Information/_restore...
4 files are from google C:Documents and settings...Google crash handler.exe, Google update.exe, GoogleUpdateSetup.exe (2x)

Do you think this is a virus or false positive?
I found here, that system volume information is a system restore program, so I disabled it. I don't know if I can clean the temporary files since I have a full sandbox.
I'd like to upgrade my AV to a more recent version. Will the files in sandbox remain there, or will they empty?

Any help apreciated

[Pondus]

Full sandbox.     Avast 4.8 does not have a sandbox!

[mateyav]

sorry about bad frazing...I use slovenian language version. I meant virus chest

[Pondus]

If You uninstall files in chest are deleted

The system restore detections should be gone if You disable system restore, reboot and enable again

[mateyav]

I better wait with the upgrading of AV then

is it possible that these are just false positives?

I dont update virus library regularly,  but I updated it on 27th and the alert came on 28th next day (auto update for the virus library is off).

[Pondus]

Why dont You autoupdate?
And why wait with upgrade to avast 7 ?

[mateyav]

Why dont You autoupdate?
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so with the auto-upgrade, the virus chest content does not delete? I need to decide what to do with the files that were found infected and are now not.

If that goes for virus library auto-update...It usually starts in a bad time, and laggs the computer, so I prefer to do it when It's more convenient.

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And why wait with upgrade to avast 7 ?
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Just reading about new versions that are not working or making the system unstable is giving me a headache, I prefer to stick with what I know that is working.

[Lisandro]

So with the auto-upgrade, the virus chest content does not delete? I need to decide what to do with the files that were found infected and are now not.

No, the files will stay there, in the Chest.

If that goes for virus library auto-update...It usually starts in a bad time, and laggs the computer, so I prefer to do it when It's more convenient.

Well, the update process is optimized and you can configure how minutes it occurs for the first time (after booting).

Just reading about new versions that are not working or making the system unstable is giving me a headache, I prefer to stick with what I know that is working.

Well... right now it's working like a charm in millions of computers. For sure you won't be in the first ones to use version 7

[mateyav]

Pondus and tech thank you for your help.

I have one more question. 
I downloaded malwarebytes anti-malware and did a quick scan. Is it possible to get it to scan the files in virus chest and how.