Need info for Backwards Compatiblity!!

Hello everyone, I decided the other day to pick up some of the original xbox games to play. I never played xbox before because I was either to busy to play games or was playing PS2. Now that I have moved on to the 360. I decided to get some games that where original classics. So my dilemma is I bought them used and have a 30 day grace period. If they do not work I get to return the ones that Do not work. Here is a list of the games I bought, and if anyone has information on how they play on the 360 I would greatly appreciate it. if the game does not run smooth through the emulator please inform me.

The games I Bought

Halo, Halo2, Conkers live and reloaded, black, Doom 3,Conflic desert storm, Ghost recon 1, 2, summit strike, Island thunder, Rainbow 6 lock down, Splinter Cell, Splinter Cell Chaos theory, Splinter cell Pandora tomorrow, Tony Hawk 4, Mercenaries, Red Dead Revlor. If there is any problems on the emulator for the 360 please let me know.

Thank you agian.

Yes those games are backwards compatible, But what I am needing to know if they play smoothly, or if they have problems. But they are able to be played in the 360. I just do not have the time to play all of them in 30 days to see. And if somebody has, they can let me know so I can take them back.