problems with wp supercache & rss feed now not validating

I have had wp super cache plug in wp for a year but had to deactivate it because it wouldnt worki with old wp. I upgraded wp to 2.7.1 on weekend & activated wp supercache & my rss feed broken now. I couldnt even deactivate supercache thru firefox 3 without getting white screen for my whole blog & managed finally to deactivate on Google Chrome. Rss still broken so have been trying to delete wp supercache file but immediately get white screen & blog disappears. This plugin is insidious????? Anyone can offer any suggestions so that I can get rid of it totally without losing my blog? My rss feed is not validating again https://www.astramatch.com/blog/wp-rss2.php . Please help