speedrun tips n stuff

[duh]

[4shockblast]

Two recent threads discussing aspects of speedrunning:
http://www.doomworld.com/vb/doom-speed-demos/65493-physical-setup-for-a-speed-run/

http://www.doomworld.com/vb/doom-speed-demos/64680-improving-speedruns/

More links in the comments for the second one by Grazza. PrBoom+ is the semi-official port for non-vanilla speedrunning since more advanced ports (such as ZDoom or GZDoom) will probably generate less viewers, and PrBoom+ is comfortable to record on because of the advanced HUD, good vanilla compatibility, and easy-to-use TAS features if you are making a TAS run.

I assume you mean unintended shortcuts by bugs. There are many tricks for vanilla Doom: glides, keygrabs, linedef skips, hitting switches from above or below, strafejumps, rocket jumps, etc. You could probably get the specifics of each trick by searching the Doomworld forums through Google, describing how to do all of them would be difficult in one post. Here's a few threads that discuss tricks:
http://www.doomworld.com/vb/doom-speed-demos/52568-the-two-types-of-glides/

http://www.doomworld.com/vb/doom-speed-demos/34928-how-do-you-perform-a-glide/

http://www.doomworld.com/vb/doom-general/54644-plasma-bumping-grabs-and-how-to-perform-them/

http://www.doomworld.com/vb/doom-general/54442-found-something-interesting/