I don't think you'll be able to hook up your Bose speakers to your computer, at least not effectively...BOSE is usually in "their own little world" as far as compatiability goes.
Do I have speakers hooked up (a resounding) YEAH!...I actually don't use my speakers on my computer for much more than websites that paly sound...I am a bit of an audio snob (I guess) I have a very extensive HT set-up (Kenwood, Marantz, Infinity, Sony) just under 700 watts, so I'd much rather listen to music on that than my $69.95 Harmon Kardon computer speakers/sub.
BUT, I do understand the need for quiet enjoyment as well, so late at night when the kids are getting along to bed, I'll usually enjoy my music via my wireless headphones. These are really cool for people who like to listen to music late at night, and need to move around the house, or be in a room where the stereo is not. They work great! Just a word of caution if you look for them get the RF (Radio Frequency) ones, not the Infrared...the infrared only works line of site...my RF one's will work down the street from my house.
Also as far as hooking up your computer dvd player to your tv it is possible (unlikely) but in some cases to get alot of interference from the computer on the tv.
I have my subwoofer that I hook up to my computer but instead of the cruddier speakers I had with them, I have my older Aiwa speakers hooked to them. Sounds good 
). Okay, well, I haven't really ever recorded anything off TV. Maybe a theme song or two, but that's it. But it sure sounds good to have the tv/dvd/vhs going thru the stereo. I have 2 bose speakers in here & may add 2 more. All I need in here is a bathroom & kitchenette & I'll never have to leave this room.... 
