The following is about facelift models only, post 1999 'V' typically;
GLS from 1999 to 2002- Front elec windows, cloth seats, black trim in doors and centre console surround, single CD player. The entry level model, available with all engines except the 3.2. 2002 onwards had rear elec windows, and wood trim.
CD- In addition to GLS, front fog lights, heated seats, velour rather than cloth and wood in all years.
CDX- In addition to CD, Xenon headlights, cruise control, sunroof, different style of alloy wheel, but still 16''.
Sport- Looks like an MV6 both internally and externally, but has the 2.2 petrol engine, has headlight washers but no xenon's
MV6- 2.6 or 3.2, all electric windows, silver trim on doors and centre console, recaro interior. Most have CCR 2006. 17'' alloys.
Elite- Cruise, heated seats, electric memory seats, leather standard on the 3.2's, auto dim mirror, wood trim, 17'' alloys, boot spoiler same as MV6, self levelling rear suspension, rear heated seats, all electric windows. CCR 2006 standard on 2.6, sat nav (NCDC 2013) standard on 3.2, with the option of the 2015, and GID with an upgrade to a CID.
There will be things I've missed, but those I think are the basics and give a general idea of the differning spec levels.