System freezes incessantly

Everyday, especially, whenever I use a download manager, Vista starts freezing and un-freezing with the mouse freezing in its place and shooting across the screen when Vista un-freezes. The download speed falls dramatically (~650 KB/s to ~250 KB/s) every few seconds coinciding with the freezing and un-freezing.

It's not the fault of the download managers, they're not out-worldly, Vista incompatible softwares; I've also tried multiple download managers, Flashget 1.73 and Internet Download Manager (latest) are the ones I am using presently.

Whenever I use these download managers, at the most a browser and iTunes are running, apart from the standard background processes.

Considering my system specs, this is mind-boggling. Secondly, this skipping and freezing never occurs on my brother's laptop in using these softwares even though its specs are half of what mine are, and we both use Vista Ultimate.

My system specs:

 

i purchased a gateway laptop a few weeks ago. it freezes up so much. i think its the HD .But i bet its VISTA.mines freeze more online or media player is going. i reduced to 16 bit resolution and tons more stuff.Office Depot is hating on me.If i cant get XP PRO/home . i will toss my 900$laptop into the river as a disgust to MICROSOFT!

 

I too would ditch my Windows Vista PC for an iMac in a heartbeat if I didn't dislike the iMac's display.

 

Think it's a VISTA thing instead of a laptop/PC manufacturer thing. I have 2GB memory and the memory shows about 51% at all times. Something is wrong, but haven't narrowed down what it is. Hope someone that has used VISTA home premium longer than I have has some ideas. I will not throw the laptop in the river as a show of disgust to MS, that would hurt me more than them. MIGHT switch to UBANTU or something similar however.