Are any of these files safe to delete???

i want to get more memory on my hard drive so a Friend told me to use disk clean up on XP and so i have and when its finished calculating what files can be delted it comes up with downloaded program files temprary internet files offline webpages Microsoft error reporting temporary files recycle bin setup... show more i want to get more memory on my hard drive so a Friend told me to use disk clean up on XP and so i have and when its finished calculating what files can be delted it comes up with

downloaded program files
temprary internet files
offline webpages
Microsoft error reporting temporary files
recycle bin
setup log files
temporary files
temporary sync files
webclient/publisher temporary files
compress old files

what i was wondering is it safe to tick all the boxes and start the clean up and then after it finishing finding that most of the files i want are deleted, will this happen???

and btw my OS is windows XP and alos what does each of them mean for example what does temporary files mean? and what will happen if they are deleted?
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