October should be perfect. You could run into some snow even? That's a great time to go down there, though. You might even get some local tour guides at that time of year? I hope I didn't infer that you would be disrespectful to the trails. The fact you're on a "foreign" bulletin board says that you're trying to get some solid information so you can have a good experience. Seems like you're a responsible user for sure? Some users are quite respectful of their local trails, but their local trails are 60' wide or something. I think of ours as 15' wide and try to stay in the traditional trail path (tough to do without knowing what that is).
D44's and 35" tires should be OK for most things. I'd imagine you could run almost ANY Moab trail with those but you should be prepared for breakage if you're stock shafts/joints. Alloy stuff is actually pretty tough and survives pretty well esp. with 35" tires. I'm not sure I'd run some of the BFE trails (there's a few I'm not interested in seeing my rig on but it's fun to watch other people
) with a stockish D44 front (some trails my one ton "Jeep" avoid as I'm a puss and don't want to work on my Jeep, just drive it). I've never run a D44 front but ran the 297/760 joints in my 4 or 5 D30s in my old XJ 35" MTRs. I did OK with snap rings, 760 joints and stock TJ takeouts with a moderate driving style. The shafts would last about 20-25 trail days? With the clips, 297 joints and stock shafts I'd only get about 10-12 trail days out of a shaft/joint combo. Welding the caps worked OK and added a few extra days to a set of shafts, I just didn't dare run the welded caps on my daily driver XJ. I don't see much wrong with a D44 rear at all as long as you know it's source vehicle in case you do break a shaft (hopefully it's a common TJ, XJ, MJ size as I've had acquaintances have a hell of a time finding a Waggy or early CJ D44 shaft in a timely manner)
If you tackle everything, there's nothing wrong with a relaxing day watching other peeps break their junk out at BFE or heading into Arches Nat. Park, Dead Horse Point, the dinosaur tracks north of Arches, a cruise up the highway along the Colorado River or something similar. There are literally thousands of attractions around the area. The more places I go, the more places I want to check out. You'd think the list would be getting smaller?
Pickle and Mashed Potato are pretty interesting trails and scenic at the same time. There might be a couple spots on Pickle that are not H1 friendly (I'm sure some badass H1 driver has tried and I bet there are pics somewhere? I'd assume there would be some body damage but I've not spent any time with H1 guys anywhere due to mostly their attitudes. I'd be interested to see the rigs in some spots, but don't want any part of trying to recover a wedged 8-10K lb rig on some trails
) but I think Mashed Potato would be totally fine for an H1 and is pretty cool.
Cliff Hanger and Metal Masher are closer to town and have "overlook" type views. Moab Rim is a worthy trail and looks out over Moab itself. Not a long trail either if you just bust up to the overlook and turn around. Cherokeester is correct below that Top of the World and Rose Garden Hill are not that popular as they are away from town and not heavily traveled. Moab Rim's a good evening or after dinner trail.
Behind the Rocks is somewhere I've seen H1's. I didn't stick around to see how/if they got through the trail, though. I think "Hummer Hill" is out that way? Fun trail with some good obstacles. This site has a TON of pics in the Trip Reports section for various EJS events. My site has a ton of pics and incredibly interesting narrative of some of the trails (
www.marbryson.com).