some installs don't work

directly to the stick?
cause that doesnt work most of the time without corrupting the file...

Download it to the desktop instead and run it from there.

It's too bad you aren't having a problem with one of the new installers that is signed, that way you'd be able to see right away if the installer you are running is corrupt or complete. If you suspect the installer might be corrupt, delete it and download it again.

Since these programs are portable, you can "uninstall" them by simply deleting the folder(s). Have you done that as part of your troubleshooting, before trying another install?

It sounds like you've been having some bad luck with your installs. Have you tried running an error check on the USB drive, to make sure the filesystem is okay? You can get there by right clicking on the drive icon in My Computer and choosing Properties | Tools.

That 0xc0000005 error seems most often to be "access violation". Since the Portable Apps programs don't require Admin access to install (as long as the user has access to the filesystem) that Admin privilege is not likely to be the issue. Maybe two programs are trying to access the same folder (directory) or file at the same time? To check that you might need to use Task Manager or Sysinternals Process Explorer to see if a hidden copy of some program might be running without a window.

What filesystem do you have on the USB drive? If it is anything other than the standard FAT32, you might mention that. If we are troubleshooting NTFS we could be getting into access or permissions issues.

An antivirus program might be causing a problem -- if the AV is trying to scan things being installed, they may not be accessible during the scan. Normally that is not a problem, it just slows things down until the AV finishes scanning.

Any other clues you can give us? What are the names of the files that seem to be cluttering folders? Have you unchecked the Explorer option to "hide extensions for known file types" (at least that is what it is called in the English version of Windows XP)? Sometimes hiding the extensions can be confusing. If you can list examples of the full filenames that seem to be extra or problemmatic, it might help us troubleshoot.

Oh, can you install it to a local HDD, like C:? To do that, you don't need the PA Menu running. Just find the paf installer (e.g. on your Desktop) without your USB drive being plugged in; click on it to run it, and tell it to install somewhere in C:, for instance to c:\temp\vlc or whatever. See if the install works there. If it does, a simple solution would be to copy the files to the USB drive -- the installer is mostly a convenience, a PAM install is mostly about putting files in the right folders.