Welcome to the hobby!
Thanks!!! I thinks this might turn out to be a lot of fun.
Let me address some other things you've been told first. HP made a lot of different power supplies, some of which are great for powering ham gear, some of which are not. Like the other poster said, be sure that it is capable of supplying enough current at 13.8 volts when you're transmitting. My club has a big, heavy HP rack-mounted supply that powers an entire rack of beacons for 10m/6m/2m/70cm/33cm/23cm that draw about 20 amps on transmit.
I think we might have the same or simular PS. Mine is a Model 6434B. Its pretty hard to beat free.
Any kind of omni-directional antenna is going to leave a lot to be desired as far as range on VHF/UHF. But, if you want that kind of coverage, you trade off. Use good quality coax. LMR-400 is good, but there are many variants and knock-offs on eBay and elsewhere. Be careful!
We have to start somewhere. I have the Mil Surplus mast segments. I can't imagine it supporting a big Yagi. This set up should be pretty portable, and allow me to hit a few repeaters at lot better than my tiny handheld. I was impreSsed at the price of the LMR-400 as it seems to be runining not much more than RG-58U.
Now your questions:
1. The first thing you must ask yourself is: why are you grounding? If it's for lightning protection, there's a whole litany of things you'll want to do. Have a look at some of the lightning protection system companies' web sites (e.g., PolyPhaser). If it's for any other reason, it's probably a waste of time, and depending on your present location and planned installation, lightning protection may also be a waste of time.
i am concerned about lightning. My wife wouldn't take kindly to burning the house down. For the time being though I will plan on setting up the antennae ungrounded and using the radio out on my patio. I will take down the antennae when not using it. Setting it up or taking it down should be a ten minute job. eventually though I like to set up a permenent radio shack indoors. Maybe even a tower.
2. SWR tells you almost nothing about the range performance of your system. If you really want to know, you'll want to try using software like Radio Mobile. It has a learning curve but can tell you a lot. I think there's something similar for Linux, but I can't for the life of me remember the name so it may not exist!
SWR is probably a good place to start. Mostly though I don't want to burn up the radio. I have pretty goog confidence that I'll get enough range in VHF to keep me happy for a while. The Jpole is a $20.00 investment. and I should be able to easily set it up as a remote.
3. Google would be as much help as I would on this one. Most good ham software is Windows-based. There is some good stuff for Linux, and very limited offerings for the Mac. I own all three kinds of systems and my two shack computers are Windows/Linux machines that are mostly booted to Windows when hamming.
My main interest in software is to program the memories and such in the 7900. I have netbooks that could be booted into window, but I don't have a cdrom. The easiest thing will be to borrow my wifes laptop to program it. I am interested in digital packet communications, but I believe there is plenty of good software for that in Linux(ubuntu)
4. It all depends on what you want to do. If you're just exploring ham radio, I'm not sure I would recommend that anyone start on VHF/UHF FM. It's not nearly as popular as it was 20 years ago, so you will have a limited group of people to work with. However, if you know that you want to communicate locally and play with APRS, etc, it's a good choice.
As a beginner I only have a Technicians licence. My interest in Ham is mostly about community. I have some friends about 50 miles away that are hams and I have an interest in Emergency response. I am in a Hurricane sensitive area and I see ham radio as an important part of personal and community preparation. Long distance communications sounds like a lot of fun and I look forward to doing this some day. but for now VHF/UHF seems like the quickest/cheapest way to get into this. I am beginning to understand that any success with UHF might be spotty. but I was hopping to be able to make some use of half of my radio.
I have carried out a conversation on a handheld GMRS 15 miles away. I might be able to reach a repeater with up to 45 watts and some real height available.
Thanks muchly for the feedback I will be checking out grounding solutions even though I won't be needing it for a while.