(I posted this in the wrong place below -- sorry.)
Also, which task manager window area you looking at? Thirty items in the applications window is a lot, but in the processes window, not so much and in the services window, fairly small.
Applications: (I have zero items that start automatically). As soon as I fire them up, Outlook and iTunes will stay there for the duration of my log-on session. The "End task" button (as mentioned above) will stop an application but will nt prevent it from starting up next time. Probably the best way to manage these is to either uninstall the software package or change the application settings so that it does not automatically start when you boot up.
Processes: (I have over 100 of these at the outset). Even though my Virus scanner says I am clean, I review these periodically to see if anything has crept in that I do not want. I rarely find anything. In this case, the "End Process" button will usually stop them but may also make your computer not work as well. Software installations will often add to this list. HP puts stuff in here to "help" you. In addition, your virus package put stuff inhere -- so does Internet Explorer, various communications facilities, even part of your windows logon process is there.
Services: (I have about 200 or so of these running at all times.) These can actually be managed somewhat effectively by clicking the "Services" button. It will open up a sindow for managing services. Here you can stop a service (temporary) and then disable it (so it won't restart again). You really should know what you are doing here -- you can easily cripple or disable your computer by stopping the wrong services. Some of these are there because of the software yo have installed -- notable examples are your virus protection and stuff like SQL servers.
In short, there is no simple answer. It depends on what you are trying to do on your machine. You need to check out each and every item you wish to remove and determine how it got there and remove it from the source. Often this is by uninstalling software or at least changing its setting so it does not run at boot up time or login time.
I do not disagree with the other answers -- I just think there is more to be said. BTW, my desktop is also an HP w/ an quad four and 16G of RAM that I use for alot of stuff.
. . . . Terry.