So I think I have some major issues that I can't seem to work out myself and I would love some help!
It all started when I downloaded this rideable skateboard from modthesims2.com. I had a sim ride it and then they started to do this weird flashing thing. I really can't it explain it well! It's like sims and objects and plumbobs with get these gray lines across them like a tv kind of flashes. It will just flash for a second or two. Today, though, Don Lothario's house did it a lot, especially when I would hover over something with my mouse. I deleted that skateboard from the game and my computer entirely. (I deleted it from the recycle bin.)
The second issue is my monitor. You know how if you leave your computer still for a while the monitor will shut off, but still be on, to save power? Mine will do that during the game! I can hear the game still going and I can click things, but I can't see anything - the monitor's off! I thought it was only doing it when I went into buy mode but it did it while I was playing Don Lothario's house today.  
After the flashing began I reinstalled everything and it worked fine with just the base game but I think when I got to Seasons the flashing started again, but I can't be sure.  Seasons worked fine until I got that skateboard and then it all went downhill until I deleted it. But I think it started up again when I reinstalled Seasons. I just wish I could remember!! I installed Bon Voyage today, hopeful that my troubles would just disappear - but no such luck.
I would really really appreciate some help because I can't play my game! Thanks to everyone who reads this and/or helps me!

My System:
I have all of the expansion packs except for Free Time, both Christmas packs and no stuff packs.
Processor: Intel(R) Celeron(R) CPU 2.40GHz
Processor Speed: 2.34 GHz
Memory (RAM): 768 MB
Operating System: Microsoft Windows XP Home Edition
Video Card:  RADEON 9200 PRO ordered straight from Dell
I save the Sims on an external hard drive with a total of 190 GB and 134 GB of that unused.

Thank you and ask me anything else you need to know to help solve the problem!  :beer:
P.S. I just installed Pets, but I did it after Bon Voyage. I didn't install it when I reinstalled everything, so I just reinstalled it. Is that bad?