In terms of file system, deleting to Recycle Bin is more or less like moving. The files you delete are put into a special protected Windows directory, and potentially the whole data needs to be read and written in a other place.
On the other hand, deleting with
Shift+Del, the file is simply erased from the file system. This is mush faster, as it's not about changing the whole file, but only removing the few bytes telling that a file is there.
Plus, concerning Total Commander, as explain here : http://www.ghisler.ch/board/viewtopic.php?t=14480:
This happens when your recycle bin is very full. TC deletes one file after the other in normal mode, which takes a while when the bin is quite full.
Try to delete with Shift+Del (bypassing the bin), or using the Explorer method.
Unfortunately this behaviour cannot be changed, because Windows doesn't report which files were deleted and which not when deleting them all in one operation...