Jackson,
Go ahead and open up the printer bay door that gives you access to the ink cartridges.
1. Take the ink cartridges out and clean the heads, then stick then back in.
2. Find the "roller" that actually rolls the paper out onto the tray while its printing. Clean those with some cotton swabs and rubbing alcohol.
3. Look *BEHIND* the rollers and you should be able to find a second set that are hidden deep in the printer itself. Again, they guide the paper through the printer. See if you can clean those, too.
The streaks sound like there's dirt or ink on these rollers and they're being transferred to your paper everytime you print.
Try printing a full sheet of paper with nothing on it (no text/pics). It still happens, right?