Xbox 360 computer connection way slower than live connection?

[phaty_bo_batty_jp]

I've got my xbox 360 fitted with a wireless adapter which is connected to the wireless hub connecting to my modem. Xbox live works fine with no lagging or problems but lately (this hasn't always been the case) when ever I try to connect to my computer for "my videos" I experience really really bad connection speeds. I've disabled my firewalls, reset my router, and turned off and on my xbox to many times to count. I've got a whole bunch of movies saved to my computer that I would really like to stream to the xbox and am hoping someone might have some fixes....the only thing I've done different since this has started was installing a program "spybot" a spy ware program which I have since uninstalled. Oh yeah and I usually connect to my videos through the "my vidoes" tab instead of windows media center (thats even slower). Any help or tips would be greatly appreciated!!