Hi DeltaSystems
DavidR is correct, your operating system is virtually unrecoverable. However, this does not mean totally unrecoverable.
If you so wish, you might like to take the opportunity to get in some practice at malware fighting.
Save what you can of your data and picture / music / video files while in Safe Mode.
Run a boot-time scan - set your schedule in Safe Mode.
Firstly, turn off System Restore - right-click My Computer, go to Properties, then System Restore, check the box to turn off, click Apply, then OK.
Secondly, schedule your scan - right-click 'a' avast icon in the systen tray at bottom right corner of screen and choose Start avast! Antivirus. Once scanner (radio) is on screen, select Menu and then click Schedule Boot-time Scan from drop-down menu. Choose Scan of local disks, and first time through run a Quick (or Standard) scan with box for archive files checked. For Advanced options, select Ask for action, then click Schedule and then Yes to restart and run scan.
The boot scan may not run due to your computer being so infected, but if it does, wait for the first instance of malware to be found, then, when asked for action, select delete all and let the scanner delete all infected user files. Don't worry too much about what is deleted.
When the scan reaches the point where system files are being scanned you will be asked for action once again. This time choose to Move all infected files to virus chest and once again let the scanner do its biz. This may take a while so you will have to be patient. At times you may have to choose another option like perhaps Ignore, but use your good sense, and also probably best act on these options individually unless too much trouble. But anyway, do best to get a reasonable scan right through on this first run.
When complete, schedule a boot scan with Thorough setting, either in Normal Mode if the screen opens, or turn computer off and schedule once again in Safe Mode. Don't waste any time doing this, just go straight through and run your Thorough scan. Check archives box again, and this time in Advanced options choose Move infected file to chest / Allow delete or move. Run scan through but keep your eye on it and again use your good sense if come to any trouble spots, and just attempt to get reasonable scan right through.
Recently, I used Sophos antirootkit as an extra option, so give that a go next.
Download and run if you can --
http://www.sophos.com/products/free-tools/sophos-anti-rootkit.html. At the end of scan, Sophos shows suspect files inside the scanner and you will need to click the files to get more information, and make sure to follow directions from Sophos so you get good grasp of all the details. Sophos will either recommend or rate or something like that so you can make informed choice at cleanup time.
If you get this far you are doing well. At this point, I would download / run up to date mbam scan --
http://www.filehippo.com/download_malwarebytes_anti_malware/tech/-- and take actions at completion to remove any suspect files.
http://forum.avast.com/index.php?topic=47121.msg396918#msg396918Post mbam log here so avast forum experts can have alook at it. Most of this is for interest value and there may be some interesting things turned up, but still we're doing some practice at malware fighting mainly. So next thing to do is run another avast boot scan using the same settings as last time -- Thorough, archives, Move to chest and Allow move.
If you've got this far, you can probably open up in Normal Mode by now. But don't dilly dally about, rather post to the forum and wait for a reply.
