find huge files/duplicates?

today i had to do a restore or re-install (not sure what it's called, just not a complete reinstall)

anyhow, it seems that i have a lot less free disk space now - like 8 gigs less. any idea what could cause that? can i search for things by the file size?

thanks!

with the panic kernels that i've been getting, applecare had me restore it. i was somewhat disappointed - i got a mac because i wanted a little more reliabilithy than microsoft. hopefull this will fix the issues i've been having.

 

Thanks!

I downloaded OmniDiskSweeper, and it says that I have 10.6 GB Previous System 1 section... is that something left over from the restore? Can I delete it?