upgrade synaptic repositories lenny disaster

Hello I've blocked something somewhere...help help help! I changed the word "etch" to "lenny" in the repositories of synaptic package mananger up in the menus and now I am in dependency hell. I'm using a normal Debian setup to write this, (not 64studio) and the synaptic doesn't seem to have the same menu-possibility, so I can't re-create the steps I took. Now she just hangs on boot with a command line waiting like a hearse outside a cemetery... On boot I see : 64studio, kernel 2.6.21-1-multimedia-486 and I can chose single user mode, and login as root. when I press control D to continue, the nvidia screen flashes on and off and eventually I get a blue screen warning about "failed to start X server"- "...wherein it is written" (zappa): (in the X output) (EE) module ABI major version (2) doesn't match the server's version (0) (EE) /usr/lib/xorg/modules/input/mouse_drv.so "kbd (module required mismatch ,0) dlopen : /usr/lib/xorg/modules/input/mouse_drv.so: undefined symbol:GetM (EE)failed to load /usr/lib/xorg/modules/input/mouse_drv.so (EE)failed to load module "mouse" (loader failed, 7) (EE)no input driver matching "kdb" (EE)no input driver matching 'mouse' no core keyboard fatal service error: failed to initialize core devices then it kindly asks if I would like to see the details aswell? can anyone help?