Virus(s) and my pathetic attempts to get rid of them

Ok, lets get one point out of the way first. I am computer retarded. I pretend that I know my way around my computer, but I don't. Not really.

Ok, the problem. I have a windows xp tower my friend built for me a couple of years ago. It was great then. Now, it isn't. I downloaded tubeviewerfile.exe (don't ask), and consequently for the next week have watched my dear computer fall into tiny quivering electronic pieces. I managed to remove a lot of damage using comodo, then AVG and spybot.

The situation at the moment is that my internet is down (for the last four days. We don't have a great connection, but its never just not worked for this long) and when I try to play my beloved x3: reunion, it constantly minimises. Constantly. Like, every three to five minutes. AVG occasionally tells me I have a virus called System32\shadow, but doesn't let me do anything about it. I am now unable to uninstall AVG to try and get an updated version from my laptop (on which this message is being written) because, quote, 'Action failed for registry key HKLM\SOFTWARE\Microsoft\Windows NT\ CurrentVersion\Windows: creating registry key Error'.

My friend ran a few online scans while the internet still ran, then I downloaded spybot from my laptop and transferred it across (same with AVG, but unable to update, the update file wouldn't open). Did a few scans with spybot and he found these lovelies; Win32.Delf.uc Trojan; Win32.Joleee.K Trojan which are apparently fixed but reappear every time I re-scan. Also WS.LDPinchlE Trojan which it cannot fix due to it being in the start-up. Start-up scan also does not remove it.

Oh, dear god, please help

 

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