there seems to be a jammed or stuck door lever and I don't know how to get past it. Any suggestions? Thanks

We need much more information if we′re gonna be able to answer. What door lever are you talking about? Is it quest related?

at the very end of the inside map there is a locked gate with a lever to pull to open. when I pull the lever it say's" the lever is jammel and the gate won't open" If this is related to a quest,,I don't know>.

There is a bug with Fort Virtue's levers that you can only use them once. If you've entered the fort before and then come back, the gates are probably closed and there's nothing you can do about it. You can get around them though, you just can't get to the area in between the two gates. Is this what you're referring to?

usually with an inside map it dosen't light up or show up if you haven't been in that place before. This area is showing which may be an indicator that I have been there before. There are a couple creatures on the other side of the gate and when I try to pull on the lever to open it it just indicated the lever is jammed!! the gate looks like it is just about 25 or 50' before the end of the the tunnel.

The bug dreamed1 referred to affects at least a couple forts. Again, once you have explored it and come back, there are a couple gates where you get that message when you activate the lever. The 'jammed' message is a surefire indicator that it is this bug. Other gates and such that won't open by design give you either an 'open remotely' or 'needs a key' message. The only normal 'jammed' message you get is for a couple broken (by design) ascension devices within some of the Oblivion Gates. If you're on PC, you can just use the toggle collision command (tcl) with the command console to pass through the gate.