That sometimes happens if you don't run the wood through evenly. Do you go
through part way, stop to move your hands, and continue? Try running it
though in one continuous motion and see if it still makes those marks. If
it does, it probably means the blade and the fence are not parallel.
Fences ususally have an adjustment to the crosshair, so the reading is
accurate. Look around, it should be there; just move it over a quarter
There are jigs that clamp on to the board, and then the jig runs against the
fence. This gives one straight edge. Many books on jigs and/or table saws
should have it; check your library. If your board has one reasonbly
straight side, you probably don't need it; though you might have to cut one
edge and flip it over and do the other to get it straight.
A carefully made cut, with a good blade and a properly setup saw, should be
good enough to glue. Mine are rarely perfect, so I always run them through
a jointer once, but set at 1/32nd inch. If I didn't have a jointer, the saw
edge would probably be okay. But yours are obviously way off. Until you
fix your problem, don't even think about gluing those edges.