from dc metro area to vegas - first timers need advice

We are moving out to Vegas and plan to drive from the Washington, DC area in a mini-van. We are going to take I-70. Optimistically, we hope to make the trip in four days. We were wondering if this was at all realistic. Additionally, does anyone have any advice re: problems we might encounter and/or anything we should be on the look out for? We plan to make a minimal number of stops, but would like to see some sights along the way, are there any attractions that wouldn't take us too far afield?

[PNW Judy]

YOu would need to average about 600 miles per day to do this 2400 mile trip in 4 days. While that's definitely doable, you would need to drive about 9 hours/day to do it. That doesn't leave much time for sightseeing. As I've never driven that route except for parts Utah and parts of Colorado, I don't have much advice to give you on that. Colorado goes through some beautiful mountain areas. Once you hit Utah it's fairly flat without the scenery in Colorado.