[vujade]

offset is the amount of backspacing a wheel has from the center point of the rim
(for exampe a 52 mm offset rim that is 7" wide has about 5.5" backspacing. This is derived by dividing 7 / 2 to find the center, then adding 52 mm (or 2") = to 5.5" total backspacing)

THe problem with this much backspacing is that it will most likely rub on something (either your balljoints, fender well or some part of your suspension). So to eleviate this, you use spacers to bring the wheel back out.

Type 1 guys that narrow their front beams to get wider wheels under the front fenders usually have to use spacers to get a good turning radius back.

As far as your rim bolt pattern goes, VW used a 4 x 130 pattern on aircooled VW's from about 1968 on... a 5 x 130 bolt pattern is a Porsche bolt pattern. IF this is the bolt pattern that you have then you will be able to find more rims in this bolt pattern then if it is the VW bolt pattern.