Windows freezing and then suddenly all programs not responding.

Background: I use my computer ALOT ( I'm sure the pc genuises here would cringe at the fact I often leave my computer on for 24+ consecutive hours) but oddly enough out of everyone I know I rarley get any problems. Roughly 2 days ago I was attempting to troubleshoot a problem where a particular game on steam wasn't responding, to do such I changed the games compataibility to run in windows xp service pack 2. The game however, didn't fix. I then left the alone, but on for roughly 4 hours, and came home. Upon arriving home I found that the computer was VERY laggy, and often one or two programs would stop responding. My computer is constantly full of files I don't need, so as such to clean it a bit thinking of lagg I uninstalled ~300gigs of programs and other trash I didn't need. I then went online to see what could cause this. Upon going online things got worse. Upon opening a third tab in my browser to compare something I was viewing on this forum to pcmag.com suddenly everything went that horrible faded white indicating it stopped responding. I'll sadly admit in my weakest moment I spam clicked ( I know it's horrible and I never do it, but I'd been in an accident earlier and my patience was at an end) which then proceeded to make things freeze to the point that it required a manual shut down and restart. The computer currently is functioning slightly better, for the most part things are running smoothly but these horrible spikes still come. alot of programs won't start at all, or when they do will crash.

attempts to fix/find the problem:
- I uninstalled mcafee completly using the tool, and installed MSE
- I elimanted 90% of the nonessential start up programs
- Cleaned 500gigs of room
- Used the disk clean
- Used msconfig to start the most common offender programs in windows 7 compatibility mode
- Countless restarts

Data that you genuises can use but looks like chicken scratch to me:
I understand with common events stopping responding that eventvwr often can be of use as such the most common errors to be found are:
*Event 1012, DNS Client Events "There was an error while attempting to read the local hosts file."
Event 10016
Event 10010
Event 10007
Event 10005
Event 8211
event 8193
event 7031
event 7022
event 7009
event 7001
event 7000
event 6008
event 1026
event 1002
*Event 1012 is the most common with 368 in the last 24 hours.

Any advice on how to fix this? thanks in advanced

PS( Sorry for not posting what all of those events are in detail, but as theres no copy and paste for that and ive frozen 3 times just typeing this, I'd prefer to not type those until someone says if they're necceary

Did you use the special tool required to uninstall the MucAfee crapware? Uninstallers (removal tools) for common antivirus software - ESET Knowledgebase

This may not be enough since it is such a pernicious infection that it alone can ruin your system. Plus we would wonder about what else you have on there if you would allow MucAfee.

Is this also the original HP factory preinstalled WIn7 which is the worst possible install of WIn7 once can have, since HP has the worst load of bloatware in the industry.

You'd be better off investing now in a perfect Clean Reinstall - Factory OEM Windows 7 then stick with the tools and methods given to assure it stays that way.

Honestly I quite like mcafee, I've had countless friends who get non-stop viruses doing nothing out of the ordianary with AVG and MSE and yet i've only gotten 1 virus that passed mcafee in my entire computer-life. That said, I finally switched to MSE due to being told it could cause this lagg. Yeah I used the tool to completely remove it also.

I woulnd't mind reinstalling windows 7 and such if in the end it's the only solution. but honestly, if I do that I lose everything as I can't really afford a hard drive to hold all ~300gigs of data I have, and in order to redownload my games my internet bill would spike due to bandwidth limits.

Any other solutions?

Your files should all be backed up anyway because the HD could fail at any time.

Here's a free method to Sync, Backup and Store your Files to the Cloud with Skydrive - Windows 7 Forums

Note that you get 7gb free storage to Skydrive for each Windows Live ID.