coming from the uk to visit las vegas sept 2006 want to omcorporate a 14 day drive around surrounding areas which is the nicer state Idaho wyoming or is utah worth a look at

Definitely go east from Las Vegas to Bryce Canyon and Zion National Parks (Utah). Then drive to Grand Canyon (Arizona) (I like South Rim - there is also North Rim and you don't need to see both). You will still have some time left over - I hope others here give you suggestions.

(I just saw your other post about weather). Wyoming/Montana - such as Yellowstone National Park can get quite cold in September - as low as freezing at night, but it warms up to 50-60 degrees during day (sorry, I do not know conversion to Centigrade/Celsius). Grand Canyon and Bryce/Zion will be a little warmer.

If you go south into Arizona (Phoenix, etc.) it will be hot, hot, hot - as will be Las Vegas.

Weather.com is a good website that gives highs/lows/averages of temperature and rainfall of just about any location.

you don't have to go all the way to idaho or wyoming. from vegas you have a lot of options. no question the most surreal landscape will be Utah the slickrock country and hoodoos formations and the sandstone hills are spectacular things to see.

you may want to do a big circle. going down to the grand canyon in Arizona, then take 64 (east/north) to 160 to 163 for monument valley from there

to 191 up to moab (great town) to go to canyonlands and arches national parks then to 70 west to 24 (south/west) drive thru capital reef (stay in torrey) then take rt 12 to bryce canyon (take the 1/2day morning trail ride) then continue on 12 to 89 south

from 89 south take 9 west to zion. stay in springdale or the park. may need reservations in the park (at bryce too)

then 15 back to vegas.

this is not a mountain trip but a high desert trip, you can also head west into california and yosemite and the sierra mountains, maybe to lake tahoe. depends on what you want to see.

A great deal will depend on the exact time of year you wish to do this. Some of the roads through Yellowstone are actually closed during certain Winter months, for example.

It might also be helpful to know if you are interested in any particular sort of scenery. Parts of Wyoming are in the so-called "high plains" region and the scenery varies significantly from the more mountainous areas.