Solar Expert needed

Vince
it is a discontinued model, it is 40 watts and has no inbuilt regulator.
Yes, you could use it to 'assist' the charge of a 100a/h battery, BUT it will not replace the power used by a fridge, it will slow the discharge of the battery and will give you some inclination of how solar will work for you, if you use it while the fridge is also connected you could get away without a regulator, but don't disconnect the fridge from the system as it may cook a battery when there is no drain on the battery, use a reasonable battery guage (multymeter) to keep an eye on the power delivered into the battery when the panel is in full sun and fridge is off, keep it below the maxium specified for your specific battery.
welcome to the solar world :-)

yes,
but before you go and buy a low priced solar regulator use the panel without one first and see if you will want to invest in a similar sized or larger panel as well to add to the 40w you have now, get the feel for how it will work for you and if you are happy with it's performance etc.
You buy a solar regulator based on your panel output, so what you get for a 40w panel will not be any good when you add another panel to the system if you initially buy a low rated reg now.

I used an 80w Solarex panel for about eight years without a regulator with no problems, however I always had a fridge connected to the batteries.

There is so much to be learned about your charging system from a decent regulator as they show the individual volts, amps, and individual totals over a given time, and also where the power is being used and has also come from all shown in their LCD display, the better ones with all the 'fruit' cost $230, but IMO are definitely worth the added cost.
Check out the “Steca PR” range at the link below

http://www.stecasolar.com/en/art/uid_kategorien/0000581/id_matchcode/up_solarladeregler/id_artikel/0000092/bop/0/chksum/4fb3b55e8148d5d3226210db61141597/beetools.html

Your panel will only put out about 2.8 amps on a good day so if your battery is connected and the fridg running then there is no worry. It will not fully supply the fridg at all times but will certainly maintain your battery for at least 3 days provided that there is plenty of sunlight and you only run a compressor type fridg and one versa light orthe like.

Vince
If you are looking for a good low cost regulator for the solar panel Jaycar Electronics have one that would suit your 40 watt panel for less than $30.00 I have used this type of regulator with no problems at all Catalog number is AA-0348 and is capable of 5 amps more than double what your 40 watt panel will output.

Cheers
Treker