Performance And Internet - Memory Card Reader Doesn't Work

All of a sudden my Dell laptop (just over a year old, go figure) has started acting funny. Here's some of the issues that started happening all of a sudden -It runs super slow at times and freezing up, svchost.exe seems to be taking a lot of resources up when that's happening -The memory card reader doesn't work. It makes the noise that a new device has been recognized when I put one it, but it never shows up in My Computer. The memory card reader does appear to be working properly in device manager. -Both firefox and IE aren't loading some sites. I'm connected to the internet and some sites load just fine and others never seem to load- and it's not that the site is down. The list of sites I can't access I'm starting to discover is big, and which sites can be access and which ones can't doesn't seem to follow any pattern- I can access google & gmail, but it won't perform a search (either from the page or from the search toolbar in both IE and firefox). I can access and log into my banking sites, ebay, and other random sites (some secure, some not). But I can't access weather.com, the Neosmart forums, the Dell community forums, dell.com, and others. I can access facebook.com, but I can't log on.

My first thought was I have some type of spyware even though I'm very good about not downloading stuff so I ran a ad-aware scan and it came up with nothing. I also ran a hijackthis scan and everything was normal there too. I'd been noticing recently that some windows processes in task manager are using what seemed like a large amount of memory. I then looked my other computer and on the problem one Explorer.exe is running around 99,000 - 120,000 kb- on my other computer it only runs around 14,000-35,000, that big of a difference between the two machines (both running xp- the problem one pro on a laptop, the other home on a desktop) is not normal...........