Bad malware or virus, caused cpu crash/reimaging/data loss + MalwareBytes crashing

Hi there,
For the last maybe half a year, I have had computer problems (I believe caused by malware and/or viruses from discontinuing my use of Webroot [this defaulted into the free Microsoft Security Essentials, which I assume is not very effective? Please advise.] I am doing this to save money because I am financially strapped right now. For the same reasons of finance, I rely on downloading torrents for a lot of e-books and audiobooks, and I guess this is probably the source of many of my issues. The source originally caused my entire computer to crash, reimage itself, and I lost all my thunderbird emails, outlook data (calendar and contact details), explorer folder organization, etc. I immediately ran all the typical programs and procedures I could think of to fix these sorts of issues, including: Firefox full clearing of data, cookies, cache, firefox version update and add-on updates, CCleaner, Spybot, Ad-aware, MalwareBytes, more recently SuperANTIspyware, deleting all explorer temp files, history, cookies, etc., Disk Cleanup (C-drive), Smart Defragment Software (a Disk Defragmenter Freeware), Add/removal of unnecessary computer programs and toolbars, Microsoft Essentials Anti-virus full scans once per week, Microsoft windows updates (always high-critical ones and oftentimes even the optional ones if they seem important), System Error-checking, and Combofix.

None of these fixed the symptom of MalwareBytes (MB) crashing my computer about 2 minutes into its full scan, which leads me to believe my computer is still being hijacked by something. MB quick scan works, but nothing beyond that. Initially, MB scanning would crash into a blue screen with an error code. That’s when I started doing some research into how to fix the dreaded blue-screen and was getting nowhere. Due to time shortages, I gave up. Now during the holidays, I have some more time to revisit this. More recently it crashes without a blue screen, which might mean either the more recent SuperANTIspyware attempts or the very recent RogueKiller, TDSSKiller, HitmanPro and MGtools from the thread http://forums.majorgeeks.com/showthread.php?t=139313 are making some dent into this fix, who knows, but still, it’s not enough of a fix to run a full MalwareBytes scan successfully. So, here I am.

Attached are my logs according to the Windows XP Malware Removal/Cleaning Procedure thread (URL above). Please note: I could not find MGlogs.zip anywhere, I did an entire system search + manual search and the only thing that remotely resembled that was "msrvlog.txt." I also have a combofix log file, I just didn't have room for the upload, so please let me know if you need that separately.

My system is a Microsoft Windows XP Professional 5.1.2600 Service Pack 3 Build 2600 HP Pavilion dv6000 x86 Genuine Intel 2GB memory. I bought it in 2007 (upgraded to 2GB on my own). Is a new one a must or can I continue to use this until it dies out on me?

Upon analysis of my logs, if you could please let me know what is wrong, how to fix it, and how to prevent this from happening again, I would really appreciate it.

Thanks so much for your time and help,
Ari