Multiple viruses found on boot-time scan

Hi just wondering if anyone can help me,
I had an incident a few weeks ago where I removed some viruses (Including the Win32 virus) from my computer on a boot-time scan as the system was unstable. The regular scans do not pick up any trace of the virus. Anyway my system was fine for a while then started crashing again and I ran a system recovery to get it work again. Seemed to help for a few days then my system completely crashed (Would freeze on startup). Safe mode still worked fine so I ran a boot time scan from there and picked up a number of viruses again including the win 32 virus (I can’t remember if the Java one was there as well, I don’t think so? I don’t have the log as it was over month ago)

My question is, is it likely the viruses are not being completely removed by the boot-time scan and reseeding themselves or am I just really unlucky and after years of being virus free, I’m suddenly picking up viruses all over the place. If the boot time scan does not always pick up all the virus, how can I remove it? My computer is running now but it is really slow on startup.

I have a lot of information I need to back up to my external hard drive so can’t just reformat, would prefer to be sure that the virus is gone before backing up incase I infect the external hard drive as well.

I’m running Windows 7. The scan picked up the following viruses:
PUP: Win32:InstallCore-AM [PUP]- severity low (x 2 virus removals)
Threat: Java:Malware-gen [Trj] - severity high (x 2 virus removals)
All 4 were sent to the chest

Any help very appreciated including as to why my computer may be slow on start up (Damage to windows vs viruses still present). I’m planning on repeating a boot-time scan (Just need quite a few hours free to run it). Thanks

Here’s the Malwarebytes file I think I’m meant to supply also
Malwarebytes Anti-Malware 1.61.0.1400
www.malwarebytes.org

Database version: v2012.07.11.05

Windows 7 Service Pack 1 x64 NTFS
Internet Explorer 9.0.8112.16421

14/07/2012 8:20:53 PM
mbam-log-2012-07-14 (20-20-53).txt

Scan type: Quick scan
Scan options enabled: Memory | Startup | Registry | File System | Heuristics/Extra | Heuristics/Shuriken | PUP | PUM
Scan options disabled: P2P
Objects scanned: 233439
Time elapsed: 5 minute(s), 5 second(s)

Memory Processes Detected: 0
(No malicious items detected)

Memory Modules Detected: 0
(No malicious items detected)

Registry Keys Detected: 0
(No malicious items detected)

Registry Values Detected: 0
(No malicious items detected)

Registry Data Items Detected: 0
(No malicious items detected)

Folders Detected: 0

PUP not a virus = Possible Unwanted Program
avast is telling you that you have a program that can be used for good or bad if abused

pup scan is default off in quick/full scan…but on in Boot scan

My question is, is it likely the viruses are not being completely removed by the boot-time scan and reseeding themselves or am I just really unlucky and after years of being virus free, I'm suddenly picking up viruses all over the place. If the boot time scan does not always pick up all the virus, how can I remove it? My computer is running now but it is really slow on startup.
anything is possible.....depends what you have...if anything

and to find out that, we have Essexboy and Jeffce :wink:

follow this guide and attach (not copy and paste) logs from malwarebytes / OTL / aswMBR
http://forum.avast.com/index.php?topic=53253.0