Will this computer be able to handle Skyrim on ultra/Battlefield 3?

The GT 630 is not a gaming card. I will say no for both. BF3 probably will not even play on the lowest setting and Skyrim you may be able to play on a low resolution on a very low graphical setting. Nothing that would look to great. I would shoot for something like a GTX560Ti to play at a decent graphical setting.

If you expect to play Ultra setting on Battlefield 3, you will need something along the lines of a GTX670. My GTX580 wouldn't even handle Ultra. This is assuming 1920x1080 @60FPS.

The PC in that link also looks like a slim model. I would stay away from those if you intend to game. There are very few small form factor gaming cards, and they tend to be very low end.
 

Kamen_BG

Distinguished
The PC you linked isnt even made for gaming.If you really want a good PC you should build it on your own!

I dont know what your budget is but this probably fits in it.

PCPartPicker part list / Price breakdown by merchant / Benchmarks

CPU: Intel Core i5-3450 3.1GHz Quad-Core Processor ($149.99 @ Microcenter)
Motherboard: MSI H77MA-G43 Micro ATX LGA1155 Motherboard ($44.98 @ NCIX US)
Memory: Kingston Blu 8GB (2 x 4GB) DDR3-1600 Memory ($35.99 @ Newegg)
Hard Drive: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive ($77.99 @ NCIX US)
Video Card: MSI Radeon HD 7950 3GB Video Card ($304.99 @ NCIX US)
Case: Antec One ATX Mid Tower Case ($39.98 @ NCIX US)
Power Supply: OCZ 600W ATX12V / EPS12V Power Supply ($39.98 @ NCIX US)
Optical Drive: LG GH24NS90 DVD/CD Writer ($16.99 @ Newegg)
Total: $710.89
(Prices include shipping and discounts when available.)
(Generated by PCPartPicker 2012-07-31 12:31 EDT-0400)

That a MUCH more powerfull PC