Cannot Select Objects in Excel

[instamatic]

I have a tab with multiple graphs that pull data from the other tabs in the same file. Suddenly, though, I cannot use the select tool at all. I also can't grab the graphs, move them around, or right click to "select data." if I hover over the graph, it gives me the cross with the arrows, as if I could move the graph, but no luck. any ideas what's going on? I tried saving into a different format and sharing/unsharing the workbook to see if that helped. I am on Excel 2007. Thanks in advance for any help I can get!