Old film shooter going digital. Which Rebel?

I'm a old film shooter. I have a Canon EOS3, 17-35 Prototype lens, a 28-105 usm and also a Tameron 70-300 telephoto lens.

I bought a Olympus E-510 kit about 2 years ago and I'm really not that impressed with it.

I do a lot of available lite shooting and 75% of my shooting is done on a tripod. I'm think of going with a Relbel of some model but not sure which one to get. I just want a body and later will add some better lenses. I'm interested in image quality at possibly higher iso's. From what I have read so far it looks like the xsi would be the right body for me. Any help or suggestions would be much appreciated. Thanks in advance.