why didn't you say excel? ;)
excel can read collectl's space-separated format with no problems, you just need to open as you would any file and tell excel the fields are space-separated when it asks.
Anyhow if you want to capture disk writes/sec, -sd will show the total writes on all your disks. If all but one are idle, this should work fine, but if you have multiple disks active, -sD will get you exact numbers for each.
I don't know where -p in your command above is coming from. You need -f/temp if you want to write the output to the directory /temp. By default, if you have the compression library installed, collectl will write its output in a compressed 'gz' file, which you can always manually uncompress. Alternatively you can add the switch -oz which will tell it not to compress.
So, the command I'd consider using is:
collectl -sD -P -f/temp -oZ
then try importing the /temp/*dsk into excel without around with --sep. It's really not hard...
of you use -sd you'll have a file named *.tab instead. if you use -sdD you'll get both!