mid feb should be a nice time to hike. few people, the best snowpack at the rim if you like to ski, and the suns track is getting high enough so that the days are a bit longer. conditions, at the south rim although much milder at the south rim than the north, can still be quite cold. in january a couple years ago, i started my hike with a down parka. temps were single digits and windy. for about the first thousand feet, i used a pair of 6-point instep crampons. the trail was packed snow and ice. crampons were necessary. the snowpack which might have been two feet at the rim thinned to nothing perhaps 1500 or 2000 feet down. by the time you get to the river you will have dropped nearly 5000feet. i recall temps possibly about 50 degrees. you will have to choose the kaibab or bright angel trail for going down. both are about the same, however if you want to take two days going back up, return on the bright angel. there is a nice area to camp at indian garden. you will have to get a backcountry permit. it won't be a problem, but it does cost. if time is not a problem plan an extra day in the canyon. take lots of film. you can't take a bad photo. for the best pics make sure you have a UV filter and take the shortest focal length lens that you have. you can get limited goodies at the canteen at the phantom ranch. if you enjoy a little drink to take the stiffness out of your knees after a long downhill hike, i would reccommend taking a lot of your favorite drink. you will be very popular at the phantom ranch camping area when word gets out that you have a fifth of scotch. enjoy!