Graduate with bad grades or repeat an year?

An anonymous reader writes: I'm a CS Student within one year of graduation.
Because of financial reasons I've been working on a full time basis for the past 2 years + worked on an open source project.
This has brought me from B+ & A in my first two years of college to somewhere in the mists of C and lower.
I now have enough money to sustain myself for two years of schooling.
I've got two choices:

• a) repeat one year, repair all my bad grades and graduate with better grades but with a mark that I repeated one school year
• b) graduate with lower grades but with no repeated year.

I'd like to know the opinion of recruiters out there: if you had two candidates which ranked similarly during the interviews but one is of type a) the other of type b), which would you favour?