Vostro 3900 I5 Graphics Upgrade

I am considering the above machine, but need to drive two monitors in extended desktop -  note that this is for basic webpages and not intensive gaming.

Having looked around on the web for a budget card, the GTX 750 gets good reviews generally. Its capability is beyond what I require,  but it seems to be the best compromise from what I can gather.

My question is, will this fit into the above-mentioned machine?  Its length and height seem to be fine, as do the power requirements. I wonder though about the plate of the card that slots through the PC case.  it looks double width to me and I wonder if the PC case is big enough to accept this? I have had a look on the web and cannot find an answer.

I have considered the other option of driving a second monitor from the USB3 port, but this is not a clear cut option either and so I may be better considering the graphics card upgrade.

It anybody can suggest a better method,  or a more suitable card then I will be happy to consider all options.

Thanks in anticipation of your help.