trouble starting

I just found this site tonight so I hope someone can help.  I have a 2001 Discovery II with about 80,000 miles.  The problem started about 2 months ago.  When I go out in the morning to start it, it starts but there is a lot knocking (sounds like metal) and though it starts it feels like something isn't connecting.  When I press the accelerator, it will only go about 5 mph and skips some.  After a few minutes or 1/2 mile it starts to get better and eventually will run OK.  This happens every time I start it.  Spark plugs and other wiring were recently changed but it didn't help.  Don't know what else to do.  I live in Dothan, AL where there aren't many LRs and no dealership. 
Thanks for any hints, suggestions

Your check engine light must be on if it is running that bad.
Go to AutoZone and have them read your Check Engine Light codes and then get back to us.

Other then getting the codes read for free at a local auto parts store, don't drive it any more if you are not ready to replace that engine, I AM SERIOUS, you are killing that engine driving it, based on what you are describing.

wow!  I thought it felt major.  The check engine light is on.  I won't drive it this weekend and will take it Monday to have it checked at autozone.  thanks!  Will be back with the results.

AutoZone is open Sat and Sun.

Thanks! I'llcheck it out!