Startup disk Full (deleted stuff, but still full...)

[J.e.n.n.y.]

Hi, I'm a newbie at technology (I know the basics of stuff and can usually manage on my own). I've come across this little problem and after viewing many threads, I'm still not too sure I understand how to solve this problem. Please help!

Basically, I've been recording my class lectures for 2 semesters on Garageband. Recently, my computer has been telling me that my startup disk was almost full. I checked the sizes of the files and realized that all the Garageband files were on average 600MB each. I copied those on an external drive and deleted them on my mac (moved to trash and emptied the trash). However, it keeps telling me that the startup disk is almost full.

I went on Disk Utility and it says that I have:
Capacity 148.7 GB
Available 116.1 MB
Used 148.6 GB

When I deleted the Garageband files, it said that I was deleting about 62 GB (I know, it's enormous) so I was expecting that much to be freed up. I tried erasing free space but it didn't change anything.

Also, I revealed the hidden files, but I have no clue which files should be deleted and which ones shouldn't.

Please help me solve this problem!
I know it's a lot, but any advice can help!

Thanks for your patience and help!

EDIT:
I have a MacBook Pro Version 10.5.8
4GB Memory
2.26 GHz Processor

 

[nicoleleifer]

first make sure you've emptied the trash!
then if it is still appearing as full, go to disk utilities under applications-utilities, and select the harddrive and click ERASE FREE SPACE
and choose 35x. this will completely zero out that space. you may need to empty trash again after this, but it should solve your problem. it solved mine.

 

[chevy]

Erasing free space will have no effect. It just writes random data over free space.

You can have two actions:
1) Emtpy the trash (or even Force empty using ctrl key)
2) Run the maintenance scripts from a utility like Onyx http://www.titanium.free.fr/