Up until now I have used a variety of fairly decent compact cameras (film and digital, mainly Olympus). I would now like to move onto a DSLR and would like some advice as to whether it is worth my while going for an older but slightly higher end secondhand camera, or just plump for a new camera - my budget being 600-800 max to include lense(s). For example, do I go for a S/H Nikon D200 or a new D90 (or Canon 550D)?

Also influencing my thinking here is the fact I am not interested at all in video capability. With a D90 or a 550D am I paying to a certain degree for HD video when I don't really want it. Acknowledging that things change all the time - how does a 5/6 yr old 1300 camera stack up in terms of image quality with brand new 700 cameras today (with or without video)?

I do realise there is a great deal for me to learn in terms of getting to know and using an SLR. As such I am not necessarily concerned with getting (and paying for) the 'best' camera just for the sake of it, but at the same time would like the best value stills camera to start with in this bracket. If buying secondhand would I necessarily be aiming too high with a D200 rather than just a D80 to begin with? I am assuming in most cases I will notice the difference with any SLR compared to the compacts I have been using.

Hope this all makes sense!