Dave,
The 10% duty cycle @ 80 amps is rather on the low side. It indicates that the machine will only run 1 minute out of every 10 minutes. This means you'll weld for 1 minute, then you'll be waiting 9 minutes before you can weld again. The machine will heat up while you are welding and cause the thermal protection to kick in, which will shut the machine down until it has cooled down.
I'd also be cautious of self regulating wire speed control myself, but it might not be a bad thing in your case, with your lack of experience and all.
The 115 volt, 15 amp input requirements mean you'll be able to plug in to any 115 volt recepticle, provided it is fed with 12 gauge wire. You might find that your receptacles are wired with 14 gauge wire, which is rated for 15 amp service, and fed from a 20 amp circuit breaker. You could burn your house down, if your not careful. I'd check the receptacles to make certain that they are rated for 20 amps. And I'd definately make certain it is grounded correctly. You might have trouble with breakers tripping if you have anything else running on the circuit the welding machine is plugged into.
The self shielding wire typically produces a lot of smoke. You might want to use it outside, as it would probablt fill a small garage with smoke. But then again, with a 10% duty cycle, it might not be an issue.
The wire will also produce a lot of slag, making it more difficult to see your weld pool.
This might suit your needs, as I'm sure the price is right. But remember, you get what you pay for.
If you've never welded before, there are some safety concerns I think you should be made aware of.
Get some safety glasses and wear them! The arc rays produced during welding contain a lot of ultraviolet radiation. This will burn your eyes and skin, and anybody else that is standing around. In effect, you will get a sunburn in no time flat. The effect on your eyeballs is called welding flashes. And it is a horrible experience, feeling like someone dropped a hand full of sand into your eyes. Your eyeballs become covered with a myriad of tiny blisters. You won't know it for several hours after you've burned them. The flashes typically only last for a day, but it'll probably be the worst day of your life! Safety glasses are your best protection.
Chipping the slag is another reason to wear the safety glasses. The slag is very hot, moving fast, and can do serious and permanent injury to your eyes. This also applies to the use of any power tools, grinders and the like. If your going to paint the end tables when your done welding them, then you'll want to be certain that you've removed all the slag so you can get a good bond with the paint. Give the welded areas a good brushing too.
I doubt if the welding hood that is supplied with the machine has a flip up lense. Purchasing one that does wouldn't be a bad idea. It gives you some good protection while your chipping slag or grinding.
If you should be unfortunate enough to get something in your eye, get it removed as soon as you can. Your eyes heal very rapidly. If you leave something in them overnight, the foreign body will likely have to be drilled out, not a pleasent experience, to be sure.
The hot slag is also a fire hazard. again, you could burn your house down if your not careful.
I don't want to go on all day with this. And I don't want to fill your head with scare tactics. A lot of people weld sucessfully without getting injured on a daily basis. Just be careful.
Hope this helps you.
Dale Simonds

Thanks very much for your detailed reply!

Regards,
Dave

Dave, I agree with everything Dale said. I just got a Lincoln 110 volt unit, wire feed, with the flux core wire. On sale for $395. I looked at Harbor Freight and other units, but by the time I added in the extras (variable settings, variable wire speed, set up for gas, etc.) I came out ahead by spending a little more. The flux core works great, but I just added the gas and it is a big difference. If you are going to do more with this welder, step up a little and you will be a lot happier.
Good luck.
Ed

i like looking for bargains, but when i see a whole welder set up for sale at $139, i'd be kinda leery. but then again, it's $139...if it doesn't work that well, you can return it pretty easily, or keep it around for something to look at and get something a little better. hehehehe anyway, i got a Hobart Handler 135 (a couple features more than the one you're looking at) and it was like $529.