where can I dump dead PC parts such as hard drive, DVDRW, motherboard? I don't want to dump parts in landfill since they don't decompose at all.

Check with your local recycling program. If they don't take them then they can most likely tell you who can.

The local computer store takes our hardware for recycling. If I remember correctly, they charge $5.00.

Some companies like Dell have free recycling programs as well.

Be very careful when you get rid of a computer, even when you delete (or think you have) everything from the hard drive, a good computer nerd can supposedly bring everything back, setting you up for identity theft bigtime. The brain of my old laptop has an appointment with some 00 buck...

So what is the best thing to do? Remove the hard drive and personally destroy it?

Well to answer the real question, when you format a harddrive or even Fdisk it you are only droping the MASTER BOOT RECORD (MBR) to actually remove all data from the harddrive you need a program that will over write the current binary data on the harddrive, i.e. replace it with all 1 or 0 or some combination there of. If you look you can find such a program. I would just write my own.
cheers

In the past I've used this method on computers at work:

Step 1. deleted all my files
Step 2. filled up my harddrive with copies of the same big file
Step 3. de-fragged the drive
Step 4. deleted the files
Step 5. Repeated steps 1-4 four or five times

My employeer frowns upon kinetically erasing the harddrive with lead pellets.

-Blast

"...My employeer frowns upon kinetically erasing the harddrive with lead pellets..."

Too bad, I'll wager that it works...

There are plenty of options out there, one I use is called DBAN (Darik's Boot And Nuke). It can be written to a CD-ROM or floppy disk. You boot off of it, and a few choices later you can be performing anything from a simple one pass zero-out wipe to a long 35 pass random type wipe. I personally go for the DOD-short method which, in 3 passes, writes random bytes, then the binary inverse of those bytes, then blanks the drive.

http://dban.sourceforge.net/

I never send a computer with a working drive to the scrap pile without running this (or BCWipe which does a similar thing).

Now if the drive is dead, I just take it apart. I then use the powerful servo magnets already in the drive and hold them up to various places on each platter, then take a hammer to them. Or... for the drives with glass platters, I simply shatter them ;-)

For those who enjoy the kinetic method - I had a co-worker from a prior job that took a couple drives out to a "shooting range" along with someone's .50 caliber rifle. Even at 100 yards, the drives didn't stand a chance. Shot through the top, the round made a nice hole clean through. Shooting through the side (read: thick) simply causes it to "explode" into many pieces.

Try this:
http://www.killdisk.com/
it is a LOT easier. I have a life.