R help - May 2009 - Some questions about package "pastecs" and "stats"

My goal is to remove signals trend without any a-priori knowledge of the trend
type, if any. Some signals are very noisy and non-stationary (example attached).
I have experimented with a number of techniques. Staring at the results, I can
hardly tell which method is best.
I am attaching the result of function "local.trend" as I cannot
understand it. Nor I can make a sense of the returned numerical data. I also
tried function "trend.test". Neither one help me detect the presence
of non-linear trend.
I would appreciate some suggestions / answers / literature refereces (possibly
in English) about the following problems (I am in the
process of learning):

1. General question:
    What are the tests that reveal the presence of trend, besides Kendall-Tau,
ACF, Lagged Scatterplot ?

2. General question:
    Is there any way to rank the goodness of trend removal ?
    In short, how can I know I have removed all the trend (the residual is a
trend-free signal)?
    For instance, a package implementing SSA, sometimes enters an endless loop.
It keeps detecting trend in the residual signal
    no matter how many times the removing procedure is run and the signal
reconstructed.

3. Question about package "pastecs":
    Are there any criteria helping with the choice of proper values for
parameters "order", "times" , "type" for functions
    "decaverage" and "decmedian" ?

4. Question about package "stats":
    Are there any criteria helping with the choice of proper kernel shape
("daniell", "dirichlet", "fejer",
"modified.daniell") and order
    and  dimension ? 

Thank you in advance.
Maura
    












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