transmission problems, help!

91 mr2 turbo
when you are driving, the transmission will not allow me to put the car in 3rd gear, 5th gear, and reverse. The other gears are getting progressivly harder to get into. 2nd gear seems to be the only one that works well. i got under the car and disconnected the two linkages on the transmission. The arm on the transmission that is closest to the ground will shift fine (rotating right and left) The arm that is higher up seems to be stuck in place with very limited movement. What is going on here?? Any help or insight would be GREATLY appreciated
thanks
Daniel

[edit] I have the clutch in while I am moving the arms of the transmission

was it shifting fine before, or has it always been like that since you bought it? possibly clutch lines need bleeding, if it won't properly disengage then it won't shift (like if you try to shift without the clutch) I had that problem a bit... otherwise there's something inside the trans shift linkage that's sticking/binding, possibly pieces of a destroyed synchro from a really bad (previous) driver, clutch dust etc... try bleeding the clutch first before anything else, and check your clutch master cylinder for leaks.