How to make D partition active?

[bagglo]

I am not sure as to where to even begin this, but here goes..I have to save all the programs and data on this HD, new, used Xcopy, to copy old HD to New,copy went fine, updated IPE and all went to he$#.. said 374 infected files, so the program changed the file names, now nothing works correctly, I've changed as many as I can find but I know I must of missed a few,can't reinstall windows, all kinds of errors, and as I said a clean install is out of the question, now this HD is a 40 gig, partitioned into 4- 10gigs (approx)..question, can I made the D part active and do a clean install there, and copy the programs and data from the C.?? the hard drive is "clean" now of infection, seemed to be a bad install of IPE,, also in bios I don't seem to have a option to boot other than "Hard Disk", so would I have to make C; inactive and then the machine would boot from D partition?? and then copy D back to C and make C active..Am I close..any advise appreciated!! Thank you!!