Ever notice that the most common question people have is why their computer slows down over time? I run ad-ware and virus programs and still it's noticeable how much it has slowed. Any general ideas welcome plus two specific things: Can running more than one virus/ad-ware program slow it down, and 2) ever so often my hard drive seems to take off for several minutes of continual work for no obvious reason during which time everything slows to a crawl.