While you're browsing there's a soft knob for 'delete'.
Hey trock,
a deeper look at both manuals would help 
Also, feel free to d/l the pdf from my sig. You'll find the URL for downloading the second manual in case you've missed it, and many tricks for file managing in the Profiler 
Use the Favorites flag on the profiles to help you.
1. Make a full back-up of your KPA
2. Browse through the favorites you already have flagged and unflag any of the ones that aren't really favorites
3. Flag the profiles that are your real favorites
4. Perform a "delete all non-favorites" (System menu)
5. Power-off the KPA and then power it back on
Now you'll have only your favorites left in the system. If you want, at this point you can re-load any profiles that you want to have always available to build on (e.g., the factory profiles, any profiles you purchases separately, specific profiles that you like from the Rig Exchange, etc.)
HTH!
Take a break. Meanwhile read through this thread: Work Flow Help Some very useful thoughts on how to sort out the tones you need / want. Go back to playing guitar. 
This has everything you'll ever want to know on this topic:
http://www.wikpa.org/Rig/Preset_Management
What I did was marked all the ones I wanted as a favorite. There are two ways to do this. One is to hold the Rig button down (this will toggle the favorite status - make sure the message says added, not removed, from favorites). The other is to go in the system menu and make sure the option is checked to automatically make a rig a favorite when you save. Then just go through the rigs and save each one you like. Then use the delete all favorites button in the system menu.
Another way is to make a backup to your usb stick, then load it on a computer, change the backup's file extension to .rar or .tar, then use 7-Zip or some other archiving program to open the archive. Then you can just delete the rigs out the backup (you'd have to know which ones are keepers vs. throw-aways using only the file name), then change the extension back and restore the KPA from backup.
There is also a free tag editor program that will convert a backup to a spreadsheet (csv) file, and then you can view all the rigs with their full tag information (actual rig name, rig author, amp profile details, cab profile details, etc.). This will help you determine which ones to delete possibly. I believe the program allows in place editing, and will convert the csv into a new backup file. So you could delete straight from there.
