whats the best Cinda of track should be used for a ho scale layout ?
Nickel-silver is the best (requires least maintenance for optimal performance), but with a little work brass and steel can work well. No matter what type you use apply some conductive lubricant sparingly to the track every year or so for best results.
Track buyer's guide
Model Railroader, October 2003 page 90
choosing track for your railroad
( "HEDIGER, JIM", REVIEW, TRACK, HO, MR )