Do you mean the scanner can store up to 400 barcodes before transferring any information to the computer? I'm guessing it should be possible as long as each barcode sends a carriage return signal before sending the next barcode.
You'll also need to clear the checkbox marked "Prompt for personalisation" otherwise Profiler will ask you for purchase info etc. after every barcode.
Try maybe a batch of 10 barcodes and see how Profiler reacts.

As for the online bit, yes Invelos supply webspace for a basic collection page though there a rumours of a subscription-based improved webspace. Just click on the icon that looks like a film spool to see a user's online collection.
To upload you simply go the Online menu in Profiler and select "DVD Profiler Online". Make sure you set your online collection settings (available under My Profiler above) the way you want them.