My Temp folder in XP has many files in it, and I want to free some space on my C, can I safely manually delete these files or are there steps/tools to delete its content automatically?

As it suggests, the 'temp' folder is used whilst loading/assembling programs/updates. When these have been applied, you can clear up the debris, just as you would clear a workbench in a garage after making something. Normally I would just delete these files manually; go to the temp folder, use Ctrl + A to select all folders & files, then use shift + del as this delete the files without putting them in the recycle bin!