I think that the best solutions is to use R in combination with R Studio. ( Python with the iPython notebook is another alternative, but not quite as easy or functional as R. )
What works well for me is to use RStudio's.
There are numerous ways to import excel (tabular) data @Nick Stauner provides perhaps the easiest solution using
read.csv; the limitation is that this requires the additional step of saving a worksheet as a CSV file. This is not great if your data is spread across multiple sheets. It can get tedious though there are VBA programs for saving all sheets as CSV files. Google for them. Another limitation is getting the types of the variables correct. If you use
read.csv, you often have to fix your types after importing in R.
There are a few packages that avoid these problems by allowing you to connect read/write from the spreadsheet directly or by using ODBC. Search on CRAN for excel or odbc to find the relevant one for your situation.
Interms of getting plots into powerpoint, use Rstudio's export plot functions.
export plot >
copy plot to clipboard >
copy as: metafile captures the plot to the the paste buffer allowing you to paste directly into Power Point.
As far as plotting options, R has numerous. The aforementioned ggplot2 package provides a very powerful interface for creating all sorts of plots. There are additional packages for doing hundreds or thousands of other types of plots/animations/etc. One limitation is that these are often buried in CRAN packages