Effect of 260/230 values on PCR
EDTA carbohydrates, phenol all have absorbance near 230 nm.  TRIzol reagent is a phenolic solution which absorbs in the UV both at 230 nm and ~270 nm 

Guanidine HCL used for most DNA isolations will absorb at ~230 nm also

All these things will seriously inhibit your pcr, (and lower your ratio) especially the denaturing agents like guanadine. 

All these DNA kits are different spins of a pretty similar process. 

If you have a good steady centrifuge stick to the phenol &amp; ethanol. Be certain you are drying your pellet well, but don't over dry it. I'll hear my pellet at 37 for 3-4 min to get rid of ethanol. Ethanol no good in pcr. If you hate doing ethanol precipitation (which I do) cause of invisible pellets, add a high grade bit of glycogen to your aqueous phase before the precipitation. This will make your pellet visible and is completely inert.

If your cleanup isn't the problem do an annealing  and Mg gradient and up your primer quantity.

May want to give me more info like the individual absorbance, pcr conditions, template size etc

Traditionally bead purifications gives really good purity, reason I use it for microarrays. But it's expensive and not necessary for pcr. 

Charge switch is just changing the charge of the bead by changing the ph.