I am falsely accused of sexual harrassment, what are my legal options?

After a break of four days i returned to work, only to find my entry card deactivated. After gaining entry to the office, i was escorted by four corporate security guards to an office where my manager, and representatives from peoples department told me i had been accused by a female cleaning staff who came to mop the office of asking her for sexual favors, and exposing myself to her while visiting pornographic websites. I was placed on two week suspension without pay pending further investigation.

MY ACCOUNT:
Cleaning crew was called by a staff member to clean the upstairs office. I was alone in the office when she came in to clear the garbage cans, we talked about general stuff, she complained about not sleeping in over 16 hours since this was her third shift, working two jobs, her relationship with a married employee of the company, and the demands of the job while emptying the garbage. She mentioned her birthday was coming up, and i asked if she would take the day off to celebrate, she said no because her two jobs would pay double if she came in to work. During this time i answered the radio, and phone calls that came in. At some point my friend called me over the radio and we talked about going bike riding, while talking to him, she tapped my shoulder to let me know she was leaving having emptied all the garbage cans, she did not mop the floors. I continued my work and left work at 5:30 am as usual. All this occurred 6/24/2010 between 2 am and 3 am. I returned to work 6/28/2010 and was then notified of the complaint and subsequent suspension for going on unauthorized websites, pending investigation into the allegation. I watched cartoons (non-pornographic adult cartoons) online.