Acer aspire One slow mo'

Processor:
Intel Atom
Processor number :
N270
Processor speed:

1.6GHz

Memory/Storage
Amt of RAM:
1024 MB
Hard drive:
8 GB
Card Reader:
SD, MMC, MS, MS Pro, xD
Flash-based HDD:Yes
Connectivity
Ports:
3 x USB 2.0; VGA out
Bluetooth:
No

Infrared:
No
Ethernet:
10/100/1000
Wireless LAN:
802.11b, 802.11g, 802.11n
Webcam:
Yes
Display
Graphics hardware:
Intel GMA

Diagonal screen size:
8.9 inch
LCD technology
Transflective (widescreen)
Screen resolution (max)
1,024 x 600
Multimedia
Sound hardware:
Integrated audio; 2 x speakers
Jacks:
mic-in, S/PDIF, earphone-out
Software
Operating system:
Win XP Home
Chassis
Weight w/battery:
0.995 kg
Dimensions:
249 x 170 x 29 mm
Power Supply:
Battery type(s) included Lithium Ion

Yesterday my friend show me his laptop, Acer Aspire One, which he bought few day ago. He said to me about lagging of this laptop. He says it too slow when open multiple window. After i check the spec, all ok with it....but the partition of hdd just one partition for operating system. Also it not have DVD or cd rom.... So if i want to format it, i must use external dvd rom or install use .iso in any external drive. I don't have any idea why this product lagging, coz follow the spec it support Windows Xp... in my head i just wanna format it back....Today he want to give that laptop to me for formatting.