Tiny doesn't always mean "tinny" herbert.
The speakers I use on my PC are less than 1/4 the size of that Logitech system.
Bose Companion 3, and the sound they push out is good.
Life goes on already told you the best option is an AV Receiver, and I have to agree.
Pick one up second hand for $50 to $150, which you can plug in headphones, or speakers, stereo, or surround, whatever you want, with sound quality as good as is deliverable by the worst component in the setup.
If you have HiFi headphones, then AV receiver will deliver the best sound, BUT, if you just want convenience then a unit like this wireless sennheiser RS 120 will do the job, for about the same as you would spend on a receiver. Cords hanging around are a pain in the bum when watching telly, especially in bed.
http://headphones.com.au/psingle?productID=78