Replying to Some Computer Help Please

If you're an asshole or have no desire to help me please go elsewhere.

I probably should have come here before I did this but, I'd like to know how what I did will fix my computer. If you have knowledge regarding computers and cleaning unnecessary files off them, I'd appreciate your help.

I use Windows XP

Lately my computer has been running really slow and lagging on almost every program I use. So tonight I was going through my Add/Remove Programs getting rid of stuff I don't use. After getting rid of some stuff I went into My Computer to fish out the rest when I cam upon a folder called "quarantine" When I think of quarantine, thoughts of sick people being hidden away from healthy people come into my head. So I figured, these files must be the ones that my school's virus scanners pick up. So I selected them all and deleted 29,902 files, roughly 120,00KB's of what I believed was crap slowing down my computer. After about 10 mins. of waiting for my computer to delete everything, I emptied my Recycle Bin and restarted my computer. After the restart my computer has been running much faster than it was before. Everything started up quickly and I can move between programs with no delay.

Although I am happy with what has happened so far, was this the right thing to do? Did I actually do something good for my computer???

Thanks