To find all your duplicate files:
ToniArts EasyCleaner 2.0.6.380 (free)
http://www.download.com/ToniArts-EasyCleaner/3000-2094_4-10522776.html?tag=lst-0-2
Do not delete system and program files or you will be very sorry.
In options click on "duplicate file options" tab
I use "same contents" regardless of name and date
There are also same name, same size, and same date and time options.
Then click on "duplicates" button. Double click on drive and set directory to search. Then click search. You manually have to select which duplicate file found you want to be deleted.
========================
When you delete a file windows marks the space that was used by the file as available space for storage. Any recovery software can recover these deleted files if performed soon after deletion. Later as files are added and moved around there is a possibility the deleted file will be overwritten with new data and become unrecoverable.
There is software to take the files you want to delete and overwrite the file making them unrecoverable.
====================
Increase Hard Drive Free Space
1) Remove programs you no longer use.
2) Save files to CD/DVD disks and delete the files off your computer.
3) Run "check disk" check both options and restart. (runs a long time)
Run Disk Cleanup then Disk Defragment.
See: 4 Ways to Speed Up Your Computer's Performance
http://www.microsoft.com/atwork/getstarted/speed.mspx
4) Install CCleaner: Do not install toolbar option
http://www.ccleaner.com/
Removes unneeded files, history, tracking cookies
In options.
Set to run when computer starts.
Place cookies you want to keep in save list
5) Update Java or download at
http://www.java.com/en/download/manual.jsp
Remove all but the latest version of java from add/remove programs. then go to Program Files\Java remove directories of older versions. (jre1.5.0_08, jre1.5.0_09, etc.)
6) Reduce space allocated for system restore to about 2 GB
start> Right click on my computer icon.> choose properties> in system properties choose restore tab.> move slider to about 2GB (1%?)
.
7) Right click on drive C icon choose properties > click on general tab > click on disk cleanup on disk cleanup "files to delete" click on compress old files (default is compress files not used for 50 days or more) . Highlight line "compress old files" button appears below "options". Options allows you to change how long a file must remain unused before being compressed.
8) On disk "C" properties page is the option box. to compress the entire disk.
9) Replace the hard drive with one with larger capacity, or add an external hard drive.
Hard drives:
http://www.newegg.com/Store/Category.aspx?Category=15&name=Hard-Drives
http://www.tigerdirect.com/applications/Category/category_tlc.asp?CatId=8