How can i speed up my internet/computer speed? I have all unnessary programs delted and i do not have a lynksis router

One of the cooling fans in my laptop (Dell Inspiron 8600) speeds up and gets very loud, it seems only to happen fairly randomly, but often. When this happens my video frame rate is extremely slow. The problem fixes itself when I restart my computer, but then happens again, randomly. Anyone know what I can do to fix this, or why this keeps happening?

My computer is running extremely show when downloading. I have currently been trying to download Aion (a game) since 1:30 pm yesterday and it is still downloading. I know its large but it should not be taking this long. My computer is downloading at 98 KBs/sec. Is there a way to speed up my computer that i myself can do, or a program that iisn’tto expensive. Help?

i bought the computer like 6 months ago and it was very fast. but now its very very slow. how do i fix it?

So here is the deal. Apparently, my computer is supposed to be "the fastest one in the house" (according to my dad). But when I was younger, I downloaded Limewire, And all sorts of different fonts and cursors from sketchy websites (I was young and stupid apparently).
Now, my computer is really slow. It takes about 15 mins to boot up, and it takes about 10 seconds to just respond to my clicks.

I have removed Limewire since then, and tried to get rid of all of the fonts and stuff, but that hasn’t really helped much.

I have Spybot and Symantec to get rid of spyware and viruses, but it is still so slow.

I would ask my dad, but I don’t want him to know that I had Limewire. >.<

Is there a software I can buy that can help me fix it? Or should I just buy a new hardrive and start over?

Thanks!